From ae3fb6df007807a37fe448fdef2b8ee669b29a5a Mon Sep 17 00:00:00 2001 From: Benjamin Feng Date: Sat, 29 Feb 2020 11:56:21 -0600 Subject: [PATCH] Copy fmtstream --- lib/std/fmtstream.zig | 1754 +++++++++++++++++++++++++++++++++++++++++ lib/std/std.zig | 1 + 2 files changed, 1755 insertions(+) create mode 100644 lib/std/fmtstream.zig diff --git a/lib/std/fmtstream.zig b/lib/std/fmtstream.zig new file mode 100644 index 0000000000..a7525ba795 --- /dev/null +++ b/lib/std/fmtstream.zig @@ -0,0 +1,1754 @@ +const std = @import("std.zig"); +const math = std.math; +const assert = std.debug.assert; +const mem = std.mem; +const builtin = @import("builtin"); +const errol = @import("fmt/errol.zig"); +const lossyCast = std.math.lossyCast; + +pub const default_max_depth = 3; + +pub const Alignment = enum { + Left, + Center, + Right, +}; + +pub const FormatOptions = struct { + precision: ?usize = null, + width: ?usize = null, + alignment: ?Alignment = null, + fill: u8 = ' ', +}; + +fn peekIsAlign(comptime fmt: []const u8) bool { + // Should only be called during a state transition to the format segment. + comptime assert(fmt[0] == ':'); + + inline for (([_]u8{ 1, 2 })[0..]) |i| { + if (fmt.len > i and (fmt[i] == '<' or fmt[i] == '^' or fmt[i] == '>')) { + return true; + } + } + return false; +} + +/// Renders fmt string with args, calling output with slices of bytes. +/// If `output` returns an error, the error is returned from `format` and +/// `output` is not called again. +/// +/// The format string must be comptime known and may contain placeholders following +/// this format: +/// `{[position][specifier]:[fill][alignment][width].[precision]}` +/// +/// Each word between `[` and `]` is a parameter you have to replace with something: +/// +/// - *position* is the index of the argument that should be inserted +/// - *specifier* is a type-dependent formatting option that determines how a type should formatted (see below) +/// - *fill* is a single character which is used to pad the formatted text +/// - *alignment* is one of the three characters `<`, `^` or `>`. they define if the text is *left*, *center*, or *right* aligned +/// - *width* is the total width of the field in characters +/// - *precision* specifies how many decimals a formatted number should have +/// +/// Note that most of the parameters are optional and may be omitted. Also you can leave out separators like `:` and `.` when +/// all parameters after the separator are omitted. +/// Only exception is the *fill* parameter. If *fill* is required, one has to specify *alignment* as well, as otherwise +/// the digits after `:` is interpreted as *width*, not *fill*. +/// +/// The *specifier* has several options for types: +/// - `x` and `X`: +/// - format the non-numeric value as a string of bytes in hexadecimal notation ("binary dump") in either lower case or upper case +/// - output numeric value in hexadecimal notation +/// - `s`: print a pointer-to-many as a c-string, use zero-termination +/// - `B` and `Bi`: output a memory size in either metric (1000) or power-of-two (1024) based notation. works for both float and integer values. +/// - `e`: output floating point value in scientific notation +/// - `d`: output numeric value in decimal notation +/// - `b`: output integer value in binary notation +/// - `c`: output integer as an ASCII character. Integer type must have 8 bits at max. +/// - `*`: output the address of the value instead of the value itself. +/// +/// If a formatted user type contains a function of the type +/// ``` +/// fn format(value: ?, comptime fmt: []const u8, options: std.fmt.FormatOptions, context: var, comptime Errors: type, comptime output: fn (@TypeOf(context), []const u8) Errors!void) Errors!void +/// ``` +/// with `?` being the type formatted, this function will be called instead of the default implementation. +/// This allows user types to be formatted in a logical manner instead of dumping all fields of the type. +/// +/// A user type may be a `struct`, `vector`, `union` or `enum` type. +pub fn format( + context: var, + comptime Errors: type, + comptime output: fn (@TypeOf(context), []const u8) Errors!void, + comptime fmt: []const u8, + args: var, +) Errors!void { + const ArgSetType = u32; + if (@typeInfo(@TypeOf(args)) != .Struct) { + @compileError("Expected tuple or struct argument, found " ++ @typeName(@TypeOf(args))); + } + if (args.len > ArgSetType.bit_count) { + @compileError("32 arguments max are supported per format call"); + } + + const State = enum { + Start, + Positional, + CloseBrace, + Specifier, + FormatFillAndAlign, + FormatWidth, + FormatPrecision, + }; + + comptime var start_index = 0; + comptime var state = State.Start; + comptime var maybe_pos_arg: ?comptime_int = null; + comptime var specifier_start = 0; + comptime var specifier_end = 0; + comptime var options = FormatOptions{}; + comptime var arg_state: struct { + next_arg: usize = 0, + used_args: ArgSetType = 0, + args_len: usize = args.len, + + fn hasUnusedArgs(comptime self: *@This()) bool { + return (@popCount(ArgSetType, self.used_args) != self.args_len); + } + + fn nextArg(comptime self: *@This(), comptime pos_arg: ?comptime_int) comptime_int { + const next_idx = pos_arg orelse blk: { + const arg = self.next_arg; + self.next_arg += 1; + break :blk arg; + }; + + if (next_idx >= self.args_len) { + @compileError("Too few arguments"); + } + + // Mark this argument as used + self.used_args |= 1 << next_idx; + + return next_idx; + } + } = .{}; + + inline for (fmt) |c, i| { + switch (state) { + .Start => switch (c) { + '{' => { + if (start_index < i) { + try output(context, fmt[start_index..i]); + } + + start_index = i; + specifier_start = i + 1; + specifier_end = i + 1; + maybe_pos_arg = null; + state = .Positional; + options = FormatOptions{}; + }, + '}' => { + if (start_index < i) { + try output(context, fmt[start_index..i]); + } + state = .CloseBrace; + }, + else => {}, + }, + .Positional => switch (c) { + '{' => { + state = .Start; + start_index = i; + }, + ':' => { + state = if (comptime peekIsAlign(fmt[i..])) State.FormatFillAndAlign else State.FormatWidth; + specifier_end = i; + }, + '0'...'9' => { + if (maybe_pos_arg == null) { + maybe_pos_arg = 0; + } + + maybe_pos_arg.? *= 10; + maybe_pos_arg.? += c - '0'; + specifier_start = i + 1; + + if (maybe_pos_arg.? >= args.len) { + @compileError("Positional value refers to non-existent argument"); + } + }, + '}' => { + const arg_to_print = comptime arg_state.nextArg(maybe_pos_arg); + + try formatType( + args[arg_to_print], + fmt[0..0], + options, + context, + Errors, + output, + default_max_depth, + ); + + state = .Start; + start_index = i + 1; + }, + else => { + state = .Specifier; + specifier_start = i; + }, + }, + .CloseBrace => switch (c) { + '}' => { + state = .Start; + start_index = i; + }, + else => @compileError("Single '}' encountered in format string"), + }, + .Specifier => switch (c) { + ':' => { + specifier_end = i; + state = if (comptime peekIsAlign(fmt[i..])) State.FormatFillAndAlign else State.FormatWidth; + }, + '}' => { + const arg_to_print = comptime arg_state.nextArg(maybe_pos_arg); + + try formatType( + args[arg_to_print], + fmt[specifier_start..i], + options, + context, + Errors, + output, + default_max_depth, + ); + state = .Start; + start_index = i + 1; + }, + else => {}, + }, + // Only entered if the format string contains a fill/align segment. + .FormatFillAndAlign => switch (c) { + '<' => { + options.alignment = Alignment.Left; + state = .FormatWidth; + }, + '^' => { + options.alignment = Alignment.Center; + state = .FormatWidth; + }, + '>' => { + options.alignment = Alignment.Right; + state = .FormatWidth; + }, + else => { + options.fill = c; + }, + }, + .FormatWidth => switch (c) { + '0'...'9' => { + if (options.width == null) { + options.width = 0; + } + + options.width.? *= 10; + options.width.? += c - '0'; + }, + '.' => { + state = .FormatPrecision; + }, + '}' => { + const arg_to_print = comptime arg_state.nextArg(maybe_pos_arg); + + try formatType( + args[arg_to_print], + fmt[specifier_start..specifier_end], + options, + context, + Errors, + output, + default_max_depth, + ); + state = .Start; + start_index = i + 1; + }, + else => { + @compileError("Unexpected character in width value: " ++ [_]u8{c}); + }, + }, + .FormatPrecision => switch (c) { + '0'...'9' => { + if (options.precision == null) { + options.precision = 0; + } + + options.precision.? *= 10; + options.precision.? += c - '0'; + }, + '}' => { + const arg_to_print = comptime arg_state.nextArg(maybe_pos_arg); + + try formatType( + args[arg_to_print], + fmt[specifier_start..specifier_end], + options, + context, + Errors, + output, + default_max_depth, + ); + state = .Start; + start_index = i + 1; + }, + else => { + @compileError("Unexpected character in precision value: " ++ [_]u8{c}); + }, + }, + } + } + comptime { + if (comptime arg_state.hasUnusedArgs()) { + @compileError("Unused arguments"); + } + if (state != State.Start) { + @compileError("Incomplete format string: " ++ fmt); + } + } + if (start_index < fmt.len) { + try output(context, fmt[start_index..]); + } +} + +pub fn formatType( + value: var, + comptime fmt: []const u8, + options: FormatOptions, + context: var, + comptime Errors: type, + comptime output: fn (@TypeOf(context), []const u8) Errors!void, + max_depth: usize, +) Errors!void { + if (comptime std.mem.eql(u8, fmt, "*")) { + try output(context, @typeName(@TypeOf(value).Child)); + try output(context, "@"); + try formatInt(@ptrToInt(value), 16, false, FormatOptions{}, context, Errors, output); + return; + } + + const T = @TypeOf(value); + switch (@typeInfo(T)) { + .ComptimeInt, .Int, .Float => { + return formatValue(value, fmt, options, context, Errors, output); + }, + .Void => { + return output(context, "void"); + }, + .Bool => { + return output(context, if (value) "true" else "false"); + }, + .Optional => { + if (value) |payload| { + return formatType(payload, fmt, options, context, Errors, output, max_depth); + } else { + return output(context, "null"); + } + }, + .ErrorUnion => { + if (value) |payload| { + return formatType(payload, fmt, options, context, Errors, output, max_depth); + } else |err| { + return formatType(err, fmt, options, context, Errors, output, max_depth); + } + }, + .ErrorSet => { + try output(context, "error."); + return output(context, @errorName(value)); + }, + .Enum => |enumInfo| { + if (comptime std.meta.trait.hasFn("format")(T)) { + return value.format(fmt, options, context, Errors, output); + } + + try output(context, @typeName(T)); + if (enumInfo.is_exhaustive) { + try output(context, "."); + try output(context, @tagName(value)); + } else { + // TODO: when @tagName works on exhaustive enums print known enum strings + try output(context, "("); + try formatType(@enumToInt(value), fmt, options, context, Errors, output, max_depth); + try output(context, ")"); + } + }, + .Union => { + if (comptime std.meta.trait.hasFn("format")(T)) { + return value.format(fmt, options, context, Errors, output); + } + + try output(context, @typeName(T)); + if (max_depth == 0) { + return output(context, "{ ... }"); + } + const info = @typeInfo(T).Union; + if (info.tag_type) |UnionTagType| { + try output(context, "{ ."); + try output(context, @tagName(@as(UnionTagType, value))); + try output(context, " = "); + inline for (info.fields) |u_field| { + if (@enumToInt(@as(UnionTagType, value)) == u_field.enum_field.?.value) { + try formatType(@field(value, u_field.name), fmt, options, context, Errors, output, max_depth - 1); + } + } + try output(context, " }"); + } else { + try format(context, Errors, output, "@{x}", .{@ptrToInt(&value)}); + } + }, + .Struct => |StructT| { + if (comptime std.meta.trait.hasFn("format")(T)) { + return value.format(fmt, options, context, Errors, output); + } + + try output(context, @typeName(T)); + if (max_depth == 0) { + return output(context, "{ ... }"); + } + try output(context, "{"); + inline for (StructT.fields) |f, i| { + if (i == 0) { + try output(context, " ."); + } else { + try output(context, ", ."); + } + try output(context, f.name); + try output(context, " = "); + try formatType(@field(value, f.name), fmt, options, context, Errors, output, max_depth - 1); + } + try output(context, " }"); + }, + .Pointer => |ptr_info| switch (ptr_info.size) { + .One => switch (@typeInfo(ptr_info.child)) { + .Array => |info| { + if (info.child == u8) { + return formatText(value, fmt, options, context, Errors, output); + } + return format(context, Errors, output, "{}@{x}", .{ @typeName(T.Child), @ptrToInt(value) }); + }, + .Enum, .Union, .Struct => { + return formatType(value.*, fmt, options, context, Errors, output, max_depth); + }, + else => return format(context, Errors, output, "{}@{x}", .{ @typeName(T.Child), @ptrToInt(value) }), + }, + .Many, .C => { + if (ptr_info.sentinel) |sentinel| { + return formatType(mem.span(value), fmt, options, context, Errors, output, max_depth); + } + if (ptr_info.child == u8) { + if (fmt.len > 0 and fmt[0] == 's') { + return formatText(mem.span(value), fmt, options, context, Errors, output); + } + } + return format(context, Errors, output, "{}@{x}", .{ @typeName(T.Child), @ptrToInt(value) }); + }, + .Slice => { + if (fmt.len > 0 and ((fmt[0] == 'x') or (fmt[0] == 'X'))) { + return formatText(value, fmt, options, context, Errors, output); + } + if (ptr_info.child == u8) { + return formatText(value, fmt, options, context, Errors, output); + } + return format(context, Errors, output, "{}@{x}", .{ @typeName(ptr_info.child), @ptrToInt(value.ptr) }); + }, + }, + .Array => |info| { + const Slice = @Type(builtin.TypeInfo{ + .Pointer = .{ + .size = .Slice, + .is_const = true, + .is_volatile = false, + .is_allowzero = false, + .alignment = @alignOf(info.child), + .child = info.child, + .sentinel = null, + }, + }); + return formatType(@as(Slice, &value), fmt, options, context, Errors, output, max_depth); + }, + .Vector => { + const len = @typeInfo(T).Vector.len; + try output(context, "{ "); + var i: usize = 0; + while (i < len) : (i += 1) { + try formatValue(value[i], fmt, options, context, Errors, output); + if (i < len - 1) { + try output(context, ", "); + } + } + try output(context, " }"); + }, + .Fn => { + return format(context, Errors, output, "{}@{x}", .{ @typeName(T), @ptrToInt(value) }); + }, + .Type => return output(context, @typeName(T)), + .EnumLiteral => { + const buffer = [_]u8{'.'} ++ @tagName(value); + return formatType(buffer, fmt, options, context, Errors, output, max_depth); + }, + else => @compileError("Unable to format type '" ++ @typeName(T) ++ "'"), + } +} + +fn formatValue( + value: var, + comptime fmt: []const u8, + options: FormatOptions, + context: var, + comptime Errors: type, + comptime output: fn (@TypeOf(context), []const u8) Errors!void, +) Errors!void { + if (comptime std.mem.eql(u8, fmt, "B")) { + return formatBytes(value, options, 1000, context, Errors, output); + } else if (comptime std.mem.eql(u8, fmt, "Bi")) { + return formatBytes(value, options, 1024, context, Errors, output); + } + + const T = @TypeOf(value); + switch (@typeInfo(T)) { + .Float => return formatFloatValue(value, fmt, options, context, Errors, output), + .Int, .ComptimeInt => return formatIntValue(value, fmt, options, context, Errors, output), + .Bool => return output(context, if (value) "true" else "false"), + else => comptime unreachable, + } +} + +pub fn formatIntValue( + value: var, + comptime fmt: []const u8, + options: FormatOptions, + context: var, + comptime Errors: type, + comptime output: fn (@TypeOf(context), []const u8) Errors!void, +) Errors!void { + comptime var radix = 10; + comptime var uppercase = false; + + const int_value = if (@TypeOf(value) == comptime_int) blk: { + const Int = math.IntFittingRange(value, value); + break :blk @as(Int, value); + } else + value; + + if (fmt.len == 0 or comptime std.mem.eql(u8, fmt, "d")) { + radix = 10; + uppercase = false; + } else if (comptime std.mem.eql(u8, fmt, "c")) { + if (@TypeOf(int_value).bit_count <= 8) { + return formatAsciiChar(@as(u8, int_value), options, context, Errors, output); + } else { + @compileError("Cannot print integer that is larger than 8 bits as a ascii"); + } + } else if (comptime std.mem.eql(u8, fmt, "b")) { + radix = 2; + uppercase = false; + } else if (comptime std.mem.eql(u8, fmt, "x")) { + radix = 16; + uppercase = false; + } else if (comptime std.mem.eql(u8, fmt, "X")) { + radix = 16; + uppercase = true; + } else { + @compileError("Unknown format string: '" ++ fmt ++ "'"); + } + + return formatInt(int_value, radix, uppercase, options, context, Errors, output); +} + +fn formatFloatValue( + value: var, + comptime fmt: []const u8, + options: FormatOptions, + context: var, + comptime Errors: type, + comptime output: fn (@TypeOf(context), []const u8) Errors!void, +) Errors!void { + if (fmt.len == 0 or comptime std.mem.eql(u8, fmt, "e")) { + return formatFloatScientific(value, options, context, Errors, output); + } else if (comptime std.mem.eql(u8, fmt, "d")) { + return formatFloatDecimal(value, options, context, Errors, output); + } else { + @compileError("Unknown format string: '" ++ fmt ++ "'"); + } +} + +pub fn formatText( + bytes: []const u8, + comptime fmt: []const u8, + options: FormatOptions, + context: var, + comptime Errors: type, + comptime output: fn (@TypeOf(context), []const u8) Errors!void, +) Errors!void { + if (fmt.len == 0) { + return output(context, bytes); + } else if (comptime std.mem.eql(u8, fmt, "s")) { + return formatBuf(bytes, options, context, Errors, output); + } else if (comptime (std.mem.eql(u8, fmt, "x") or std.mem.eql(u8, fmt, "X"))) { + for (bytes) |c| { + try formatInt(c, 16, fmt[0] == 'X', FormatOptions{ .width = 2, .fill = '0' }, context, Errors, output); + } + return; + } else { + @compileError("Unknown format string: '" ++ fmt ++ "'"); + } +} + +pub fn formatAsciiChar( + c: u8, + options: FormatOptions, + context: var, + comptime Errors: type, + comptime output: fn (@TypeOf(context), []const u8) Errors!void, +) Errors!void { + return output(context, @as(*const [1]u8, &c)[0..]); +} + +pub fn formatBuf( + buf: []const u8, + options: FormatOptions, + context: var, + comptime Errors: type, + comptime output: fn (@TypeOf(context), []const u8) Errors!void, +) Errors!void { + try output(context, buf); + + const width = options.width orelse 0; + var leftover_padding = if (width > buf.len) (width - buf.len) else return; + const pad_byte: u8 = options.fill; + while (leftover_padding > 0) : (leftover_padding -= 1) { + try output(context, @as(*const [1]u8, &pad_byte)[0..1]); + } +} + +// Print a float in scientific notation to the specified precision. Null uses full precision. +// It should be the case that every full precision, printed value can be re-parsed back to the +// same type unambiguously. +pub fn formatFloatScientific( + value: var, + options: FormatOptions, + context: var, + comptime Errors: type, + comptime output: fn (@TypeOf(context), []const u8) Errors!void, +) Errors!void { + var x = @floatCast(f64, value); + + // Errol doesn't handle these special cases. + if (math.signbit(x)) { + try output(context, "-"); + x = -x; + } + + if (math.isNan(x)) { + return output(context, "nan"); + } + if (math.isPositiveInf(x)) { + return output(context, "inf"); + } + if (x == 0.0) { + try output(context, "0"); + + if (options.precision) |precision| { + if (precision != 0) { + try output(context, "."); + var i: usize = 0; + while (i < precision) : (i += 1) { + try output(context, "0"); + } + } + } else { + try output(context, ".0"); + } + + try output(context, "e+00"); + return; + } + + var buffer: [32]u8 = undefined; + var float_decimal = errol.errol3(x, buffer[0..]); + + if (options.precision) |precision| { + errol.roundToPrecision(&float_decimal, precision, errol.RoundMode.Scientific); + + try output(context, float_decimal.digits[0..1]); + + // {e0} case prints no `.` + if (precision != 0) { + try output(context, "."); + + var printed: usize = 0; + if (float_decimal.digits.len > 1) { + const num_digits = math.min(float_decimal.digits.len, precision + 1); + try output(context, float_decimal.digits[1..num_digits]); + printed += num_digits - 1; + } + + while (printed < precision) : (printed += 1) { + try output(context, "0"); + } + } + } else { + try output(context, float_decimal.digits[0..1]); + try output(context, "."); + if (float_decimal.digits.len > 1) { + const num_digits = if (@TypeOf(value) == f32) math.min(@as(usize, 9), float_decimal.digits.len) else float_decimal.digits.len; + + try output(context, float_decimal.digits[1..num_digits]); + } else { + try output(context, "0"); + } + } + + try output(context, "e"); + const exp = float_decimal.exp - 1; + + if (exp >= 0) { + try output(context, "+"); + if (exp > -10 and exp < 10) { + try output(context, "0"); + } + try formatInt(exp, 10, false, FormatOptions{ .width = 0 }, context, Errors, output); + } else { + try output(context, "-"); + if (exp > -10 and exp < 10) { + try output(context, "0"); + } + try formatInt(-exp, 10, false, FormatOptions{ .width = 0 }, context, Errors, output); + } +} + +// Print a float of the format x.yyyyy where the number of y is specified by the precision argument. +// By default floats are printed at full precision (no rounding). +pub fn formatFloatDecimal( + value: var, + options: FormatOptions, + context: var, + comptime Errors: type, + comptime output: fn (@TypeOf(context), []const u8) Errors!void, +) Errors!void { + var x = @as(f64, value); + + // Errol doesn't handle these special cases. + if (math.signbit(x)) { + try output(context, "-"); + x = -x; + } + + if (math.isNan(x)) { + return output(context, "nan"); + } + if (math.isPositiveInf(x)) { + return output(context, "inf"); + } + if (x == 0.0) { + try output(context, "0"); + + if (options.precision) |precision| { + if (precision != 0) { + try output(context, "."); + var i: usize = 0; + while (i < precision) : (i += 1) { + try output(context, "0"); + } + } else { + try output(context, ".0"); + } + } + + return; + } + + // non-special case, use errol3 + var buffer: [32]u8 = undefined; + var float_decimal = errol.errol3(x, buffer[0..]); + + if (options.precision) |precision| { + errol.roundToPrecision(&float_decimal, precision, errol.RoundMode.Decimal); + + // exp < 0 means the leading is always 0 as errol result is normalized. + var num_digits_whole = if (float_decimal.exp > 0) @intCast(usize, float_decimal.exp) else 0; + + // the actual slice into the buffer, we may need to zero-pad between num_digits_whole and this. + var num_digits_whole_no_pad = math.min(num_digits_whole, float_decimal.digits.len); + + if (num_digits_whole > 0) { + // We may have to zero pad, for instance 1e4 requires zero padding. + try output(context, float_decimal.digits[0..num_digits_whole_no_pad]); + + var i = num_digits_whole_no_pad; + while (i < num_digits_whole) : (i += 1) { + try output(context, "0"); + } + } else { + try output(context, "0"); + } + + // {.0} special case doesn't want a trailing '.' + if (precision == 0) { + return; + } + + try output(context, "."); + + // Keep track of fractional count printed for case where we pre-pad then post-pad with 0's. + var printed: usize = 0; + + // Zero-fill until we reach significant digits or run out of precision. + if (float_decimal.exp <= 0) { + const zero_digit_count = @intCast(usize, -float_decimal.exp); + const zeros_to_print = math.min(zero_digit_count, precision); + + var i: usize = 0; + while (i < zeros_to_print) : (i += 1) { + try output(context, "0"); + printed += 1; + } + + if (printed >= precision) { + return; + } + } + + // Remaining fractional portion, zero-padding if insufficient. + assert(precision >= printed); + if (num_digits_whole_no_pad + precision - printed < float_decimal.digits.len) { + try output(context, float_decimal.digits[num_digits_whole_no_pad .. num_digits_whole_no_pad + precision - printed]); + return; + } else { + try output(context, float_decimal.digits[num_digits_whole_no_pad..]); + printed += float_decimal.digits.len - num_digits_whole_no_pad; + + while (printed < precision) : (printed += 1) { + try output(context, "0"); + } + } + } else { + // exp < 0 means the leading is always 0 as errol result is normalized. + var num_digits_whole = if (float_decimal.exp > 0) @intCast(usize, float_decimal.exp) else 0; + + // the actual slice into the buffer, we may need to zero-pad between num_digits_whole and this. + var num_digits_whole_no_pad = math.min(num_digits_whole, float_decimal.digits.len); + + if (num_digits_whole > 0) { + // We may have to zero pad, for instance 1e4 requires zero padding. + try output(context, float_decimal.digits[0..num_digits_whole_no_pad]); + + var i = num_digits_whole_no_pad; + while (i < num_digits_whole) : (i += 1) { + try output(context, "0"); + } + } else { + try output(context, "0"); + } + + // Omit `.` if no fractional portion + if (float_decimal.exp >= 0 and num_digits_whole_no_pad == float_decimal.digits.len) { + return; + } + + try output(context, "."); + + // Zero-fill until we reach significant digits or run out of precision. + if (float_decimal.exp < 0) { + const zero_digit_count = @intCast(usize, -float_decimal.exp); + + var i: usize = 0; + while (i < zero_digit_count) : (i += 1) { + try output(context, "0"); + } + } + + try output(context, float_decimal.digits[num_digits_whole_no_pad..]); + } +} + +pub fn formatBytes( + value: var, + options: FormatOptions, + comptime radix: usize, + context: var, + comptime Errors: type, + comptime output: fn (@TypeOf(context), []const u8) Errors!void, +) Errors!void { + if (value == 0) { + return output(context, "0B"); + } + + const mags_si = " kMGTPEZY"; + const mags_iec = " KMGTPEZY"; + const magnitude = switch (radix) { + 1000 => math.min(math.log2(value) / comptime math.log2(1000), mags_si.len - 1), + 1024 => math.min(math.log2(value) / 10, mags_iec.len - 1), + else => unreachable, + }; + const new_value = lossyCast(f64, value) / math.pow(f64, lossyCast(f64, radix), lossyCast(f64, magnitude)); + const suffix = switch (radix) { + 1000 => mags_si[magnitude], + 1024 => mags_iec[magnitude], + else => unreachable, + }; + + try formatFloatDecimal(new_value, options, context, Errors, output); + + if (suffix == ' ') { + return output(context, "B"); + } + + const buf = switch (radix) { + 1000 => &[_]u8{ suffix, 'B' }, + 1024 => &[_]u8{ suffix, 'i', 'B' }, + else => unreachable, + }; + return output(context, buf); +} + +pub fn formatInt( + value: var, + base: u8, + uppercase: bool, + options: FormatOptions, + context: var, + comptime Errors: type, + comptime output: fn (@TypeOf(context), []const u8) Errors!void, +) Errors!void { + const int_value = if (@TypeOf(value) == comptime_int) blk: { + const Int = math.IntFittingRange(value, value); + break :blk @as(Int, value); + } else + value; + + if (@TypeOf(int_value).is_signed) { + return formatIntSigned(int_value, base, uppercase, options, context, Errors, output); + } else { + return formatIntUnsigned(int_value, base, uppercase, options, context, Errors, output); + } +} + +fn formatIntSigned( + value: var, + base: u8, + uppercase: bool, + options: FormatOptions, + context: var, + comptime Errors: type, + comptime output: fn (@TypeOf(context), []const u8) Errors!void, +) Errors!void { + const new_options = FormatOptions{ + .width = if (options.width) |w| (if (w == 0) 0 else w - 1) else null, + .precision = options.precision, + .fill = options.fill, + }; + const bit_count = @typeInfo(@TypeOf(value)).Int.bits; + const Uint = std.meta.IntType(false, bit_count); + if (value < 0) { + try output(context, "-"); + const new_value = math.absCast(value); + return formatIntUnsigned(new_value, base, uppercase, new_options, context, Errors, output); + } else if (options.width == null or options.width.? == 0) { + return formatIntUnsigned(@intCast(Uint, value), base, uppercase, options, context, Errors, output); + } else { + try output(context, "+"); + const new_value = @intCast(Uint, value); + return formatIntUnsigned(new_value, base, uppercase, new_options, context, Errors, output); + } +} + +fn formatIntUnsigned( + value: var, + base: u8, + uppercase: bool, + options: FormatOptions, + context: var, + comptime Errors: type, + comptime output: fn (@TypeOf(context), []const u8) Errors!void, +) Errors!void { + assert(base >= 2); + var buf: [math.max(@TypeOf(value).bit_count, 1)]u8 = undefined; + const min_int_bits = comptime math.max(@TypeOf(value).bit_count, @TypeOf(base).bit_count); + const MinInt = std.meta.IntType(@TypeOf(value).is_signed, min_int_bits); + var a: MinInt = value; + var index: usize = buf.len; + + while (true) { + const digit = a % base; + index -= 1; + buf[index] = digitToChar(@intCast(u8, digit), uppercase); + a /= base; + if (a == 0) break; + } + + const digits_buf = buf[index..]; + const width = options.width orelse 0; + const padding = if (width > digits_buf.len) (width - digits_buf.len) else 0; + + if (padding > index) { + const zero_byte: u8 = options.fill; + var leftover_padding = padding - index; + while (true) { + try output(context, @as(*const [1]u8, &zero_byte)[0..]); + leftover_padding -= 1; + if (leftover_padding == 0) break; + } + mem.set(u8, buf[0..index], options.fill); + return output(context, &buf); + } else { + const padded_buf = buf[index - padding ..]; + mem.set(u8, padded_buf[0..padding], options.fill); + return output(context, padded_buf); + } +} + +pub fn formatIntBuf(out_buf: []u8, value: var, base: u8, uppercase: bool, options: FormatOptions) usize { + var context = FormatIntBuf{ + .out_buf = out_buf, + .index = 0, + }; + formatInt(value, base, uppercase, options, &context, error{}, formatIntCallback) catch unreachable; + return context.index; +} +const FormatIntBuf = struct { + out_buf: []u8, + index: usize, +}; +fn formatIntCallback(context: *FormatIntBuf, bytes: []const u8) (error{}!void) { + mem.copy(u8, context.out_buf[context.index..], bytes); + context.index += bytes.len; +} + +pub fn parseInt(comptime T: type, buf: []const u8, radix: u8) !T { + if (!T.is_signed) return parseUnsigned(T, buf, radix); + if (buf.len == 0) return @as(T, 0); + if (buf[0] == '-') { + return math.negate(try parseUnsigned(T, buf[1..], radix)); + } else if (buf[0] == '+') { + return parseUnsigned(T, buf[1..], radix); + } else { + return parseUnsigned(T, buf, radix); + } +} + +test "parseInt" { + std.testing.expect((parseInt(i32, "-10", 10) catch unreachable) == -10); + std.testing.expect((parseInt(i32, "+10", 10) catch unreachable) == 10); + std.testing.expect(if (parseInt(i32, " 10", 10)) |_| false else |err| err == error.InvalidCharacter); + std.testing.expect(if (parseInt(i32, "10 ", 10)) |_| false else |err| err == error.InvalidCharacter); + std.testing.expect(if (parseInt(u32, "-10", 10)) |_| false else |err| err == error.InvalidCharacter); + std.testing.expect((parseInt(u8, "255", 10) catch unreachable) == 255); + std.testing.expect(if (parseInt(u8, "256", 10)) |_| false else |err| err == error.Overflow); +} + +pub const ParseUnsignedError = error{ + /// The result cannot fit in the type specified + Overflow, + + /// The input had a byte that was not a digit + InvalidCharacter, +}; + +pub fn parseUnsigned(comptime T: type, buf: []const u8, radix: u8) ParseUnsignedError!T { + var x: T = 0; + + for (buf) |c| { + const digit = try charToDigit(c, radix); + + if (x != 0) x = try math.mul(T, x, try math.cast(T, radix)); + x = try math.add(T, x, try math.cast(T, digit)); + } + + return x; +} + +test "parseUnsigned" { + std.testing.expect((try parseUnsigned(u16, "050124", 10)) == 50124); + std.testing.expect((try parseUnsigned(u16, "65535", 10)) == 65535); + std.testing.expectError(error.Overflow, parseUnsigned(u16, "65536", 10)); + + std.testing.expect((try parseUnsigned(u64, "0ffffffffffffffff", 16)) == 0xffffffffffffffff); + std.testing.expectError(error.Overflow, parseUnsigned(u64, "10000000000000000", 16)); + + std.testing.expect((try parseUnsigned(u32, "DeadBeef", 16)) == 0xDEADBEEF); + + std.testing.expect((try parseUnsigned(u7, "1", 10)) == 1); + std.testing.expect((try parseUnsigned(u7, "1000", 2)) == 8); + + std.testing.expectError(error.InvalidCharacter, parseUnsigned(u32, "f", 10)); + std.testing.expectError(error.InvalidCharacter, parseUnsigned(u8, "109", 8)); + + std.testing.expect((try parseUnsigned(u32, "NUMBER", 36)) == 1442151747); + + // these numbers should fit even though the radix itself doesn't fit in the destination type + std.testing.expect((try parseUnsigned(u1, "0", 10)) == 0); + std.testing.expect((try parseUnsigned(u1, "1", 10)) == 1); + std.testing.expectError(error.Overflow, parseUnsigned(u1, "2", 10)); + std.testing.expect((try parseUnsigned(u1, "001", 16)) == 1); + std.testing.expect((try parseUnsigned(u2, "3", 16)) == 3); + std.testing.expectError(error.Overflow, parseUnsigned(u2, "4", 16)); +} + +pub const parseFloat = @import("fmt/parse_float.zig").parseFloat; + +test "parseFloat" { + _ = @import("fmt/parse_float.zig"); +} + +pub fn charToDigit(c: u8, radix: u8) (error{InvalidCharacter}!u8) { + const value = switch (c) { + '0'...'9' => c - '0', + 'A'...'Z' => c - 'A' + 10, + 'a'...'z' => c - 'a' + 10, + else => return error.InvalidCharacter, + }; + + if (value >= radix) return error.InvalidCharacter; + + return value; +} + +fn digitToChar(digit: u8, uppercase: bool) u8 { + return switch (digit) { + 0...9 => digit + '0', + 10...35 => digit + ((if (uppercase) @as(u8, 'A') else @as(u8, 'a')) - 10), + else => unreachable, + }; +} + +const BufPrintContext = struct { + remaining: []u8, +}; + +fn bufPrintWrite(context: *BufPrintContext, bytes: []const u8) !void { + if (context.remaining.len < bytes.len) { + mem.copy(u8, context.remaining, bytes[0..context.remaining.len]); + return error.BufferTooSmall; + } + mem.copy(u8, context.remaining, bytes); + context.remaining = context.remaining[bytes.len..]; +} + +pub const BufPrintError = error{ + /// As much as possible was written to the buffer, but it was too small to fit all the printed bytes. + BufferTooSmall, +}; +pub fn bufPrint(buf: []u8, comptime fmt: []const u8, args: var) BufPrintError![]u8 { + var context = BufPrintContext{ .remaining = buf }; + try format(&context, BufPrintError, bufPrintWrite, fmt, args); + return buf[0 .. buf.len - context.remaining.len]; +} + +pub const AllocPrintError = error{OutOfMemory}; + +pub fn allocPrint(allocator: *mem.Allocator, comptime fmt: []const u8, args: var) AllocPrintError![]u8 { + var size: usize = 0; + format(&size, error{}, countSize, fmt, args) catch |err| switch (err) {}; + const buf = try allocator.alloc(u8, size); + return bufPrint(buf, fmt, args) catch |err| switch (err) { + error.BufferTooSmall => unreachable, // we just counted the size above + }; +} + +fn countSize(size: *usize, bytes: []const u8) (error{}!void) { + size.* += bytes.len; +} + +pub fn allocPrint0(allocator: *mem.Allocator, comptime fmt: []const u8, args: var) AllocPrintError![:0]u8 { + const result = try allocPrint(allocator, fmt ++ "\x00", args); + return result[0 .. result.len - 1 :0]; +} + +test "bufPrintInt" { + var buffer: [100]u8 = undefined; + const buf = buffer[0..]; + + std.testing.expectEqualSlices(u8, "-1", bufPrintIntToSlice(buf, @as(i1, -1), 10, false, FormatOptions{})); + + std.testing.expectEqualSlices(u8, "-101111000110000101001110", bufPrintIntToSlice(buf, @as(i32, -12345678), 2, false, FormatOptions{})); + std.testing.expectEqualSlices(u8, "-12345678", bufPrintIntToSlice(buf, @as(i32, -12345678), 10, false, FormatOptions{})); + std.testing.expectEqualSlices(u8, "-bc614e", bufPrintIntToSlice(buf, @as(i32, -12345678), 16, false, FormatOptions{})); + std.testing.expectEqualSlices(u8, "-BC614E", bufPrintIntToSlice(buf, @as(i32, -12345678), 16, true, FormatOptions{})); + + std.testing.expectEqualSlices(u8, "12345678", bufPrintIntToSlice(buf, @as(u32, 12345678), 10, true, FormatOptions{})); + + std.testing.expectEqualSlices(u8, " 666", bufPrintIntToSlice(buf, @as(u32, 666), 10, false, FormatOptions{ .width = 6 })); + std.testing.expectEqualSlices(u8, " 1234", bufPrintIntToSlice(buf, @as(u32, 0x1234), 16, false, FormatOptions{ .width = 6 })); + std.testing.expectEqualSlices(u8, "1234", bufPrintIntToSlice(buf, @as(u32, 0x1234), 16, false, FormatOptions{ .width = 1 })); + + std.testing.expectEqualSlices(u8, "+42", bufPrintIntToSlice(buf, @as(i32, 42), 10, false, FormatOptions{ .width = 3 })); + std.testing.expectEqualSlices(u8, "-42", bufPrintIntToSlice(buf, @as(i32, -42), 10, false, FormatOptions{ .width = 3 })); +} + +fn bufPrintIntToSlice(buf: []u8, value: var, base: u8, uppercase: bool, options: FormatOptions) []u8 { + return buf[0..formatIntBuf(buf, value, base, uppercase, options)]; +} + +test "parse u64 digit too big" { + _ = parseUnsigned(u64, "123a", 10) catch |err| { + if (err == error.InvalidCharacter) return; + unreachable; + }; + unreachable; +} + +test "parse unsigned comptime" { + comptime { + std.testing.expect((try parseUnsigned(usize, "2", 10)) == 2); + } +} + +test "optional" { + { + const value: ?i32 = 1234; + try testFmt("optional: 1234\n", "optional: {}\n", .{value}); + } + { + const value: ?i32 = null; + try testFmt("optional: null\n", "optional: {}\n", .{value}); + } +} + +test "error" { + { + const value: anyerror!i32 = 1234; + try testFmt("error union: 1234\n", "error union: {}\n", .{value}); + } + { + const value: anyerror!i32 = error.InvalidChar; + try testFmt("error union: error.InvalidChar\n", "error union: {}\n", .{value}); + } +} + +test "int.small" { + { + const value: u3 = 0b101; + try testFmt("u3: 5\n", "u3: {}\n", .{value}); + } +} + +test "int.specifier" { + { + const value: u8 = 'a'; + try testFmt("u8: a\n", "u8: {c}\n", .{value}); + } + { + const value: u8 = 0b1100; + try testFmt("u8: 0b1100\n", "u8: 0b{b}\n", .{value}); + } +} + +test "int.padded" { + try testFmt("u8: ' 1'", "u8: '{:4}'", .{@as(u8, 1)}); + try testFmt("u8: 'xxx1'", "u8: '{:x<4}'", .{@as(u8, 1)}); +} + +test "buffer" { + { + var buf1: [32]u8 = undefined; + var context = BufPrintContext{ .remaining = buf1[0..] }; + try formatType(1234, "", FormatOptions{}, &context, error{BufferTooSmall}, bufPrintWrite, default_max_depth); + var res = buf1[0 .. buf1.len - context.remaining.len]; + std.testing.expect(mem.eql(u8, res, "1234")); + + context = BufPrintContext{ .remaining = buf1[0..] }; + try formatType('a', "c", FormatOptions{}, &context, error{BufferTooSmall}, bufPrintWrite, default_max_depth); + res = buf1[0 .. buf1.len - context.remaining.len]; + std.testing.expect(mem.eql(u8, res, "a")); + + context = BufPrintContext{ .remaining = buf1[0..] }; + try formatType(0b1100, "b", FormatOptions{}, &context, error{BufferTooSmall}, bufPrintWrite, default_max_depth); + res = buf1[0 .. buf1.len - context.remaining.len]; + std.testing.expect(mem.eql(u8, res, "1100")); + } +} + +test "array" { + { + const value: [3]u8 = "abc".*; + try testFmt("array: abc\n", "array: {}\n", .{value}); + try testFmt("array: abc\n", "array: {}\n", .{&value}); + + var buf: [100]u8 = undefined; + try testFmt( + try bufPrint(buf[0..], "array: [3]u8@{x}\n", .{@ptrToInt(&value)}), + "array: {*}\n", + .{&value}, + ); + } +} + +test "slice" { + { + const value: []const u8 = "abc"; + try testFmt("slice: abc\n", "slice: {}\n", .{value}); + } + { + const value = @intToPtr([*]align(1) const []const u8, 0xdeadbeef)[0..0]; + try testFmt("slice: []const u8@deadbeef\n", "slice: {}\n", .{value}); + } + + try testFmt("buf: Test \n", "buf: {s:5}\n", .{"Test"}); + try testFmt("buf: Test\n Other text", "buf: {s}\n Other text", .{"Test"}); +} + +test "pointer" { + { + const value = @intToPtr(*align(1) i32, 0xdeadbeef); + try testFmt("pointer: i32@deadbeef\n", "pointer: {}\n", .{value}); + try testFmt("pointer: i32@deadbeef\n", "pointer: {*}\n", .{value}); + } + { + const value = @intToPtr(fn () void, 0xdeadbeef); + try testFmt("pointer: fn() void@deadbeef\n", "pointer: {}\n", .{value}); + } + { + const value = @intToPtr(fn () void, 0xdeadbeef); + try testFmt("pointer: fn() void@deadbeef\n", "pointer: {}\n", .{value}); + } +} + +test "cstr" { + try testFmt( + "cstr: Test C\n", + "cstr: {s}\n", + .{@ptrCast([*c]const u8, "Test C")}, + ); + try testFmt( + "cstr: Test C \n", + "cstr: {s:10}\n", + .{@ptrCast([*c]const u8, "Test C")}, + ); +} + +test "filesize" { + try testFmt("file size: 63MiB\n", "file size: {Bi}\n", .{@as(usize, 63 * 1024 * 1024)}); + try testFmt("file size: 66.06MB\n", "file size: {B:.2}\n", .{@as(usize, 63 * 1024 * 1024)}); +} + +test "struct" { + { + const Struct = struct { + field: u8, + }; + const value = Struct{ .field = 42 }; + try testFmt("struct: Struct{ .field = 42 }\n", "struct: {}\n", .{value}); + try testFmt("struct: Struct{ .field = 42 }\n", "struct: {}\n", .{&value}); + } + { + const Struct = struct { + a: u0, + b: u1, + }; + const value = Struct{ .a = 0, .b = 1 }; + try testFmt("struct: Struct{ .a = 0, .b = 1 }\n", "struct: {}\n", .{value}); + } +} + +test "enum" { + const Enum = enum { + One, + Two, + }; + const value = Enum.Two; + try testFmt("enum: Enum.Two\n", "enum: {}\n", .{value}); + try testFmt("enum: Enum.Two\n", "enum: {}\n", .{&value}); +} + +test "non-exhaustive enum" { + const Enum = enum(u16) { + One = 0x000f, + Two = 0xbeef, + _, + }; + try testFmt("enum: Enum(15)\n", "enum: {}\n", .{Enum.One}); + try testFmt("enum: Enum(48879)\n", "enum: {}\n", .{Enum.Two}); + try testFmt("enum: Enum(4660)\n", "enum: {}\n", .{@intToEnum(Enum, 0x1234)}); + try testFmt("enum: Enum(f)\n", "enum: {x}\n", .{Enum.One}); + try testFmt("enum: Enum(beef)\n", "enum: {x}\n", .{Enum.Two}); + try testFmt("enum: Enum(1234)\n", "enum: {x}\n", .{@intToEnum(Enum, 0x1234)}); +} + +test "float.scientific" { + try testFmt("f32: 1.34000003e+00", "f32: {e}", .{@as(f32, 1.34)}); + try testFmt("f32: 1.23400001e+01", "f32: {e}", .{@as(f32, 12.34)}); + try testFmt("f64: -1.234e+11", "f64: {e}", .{@as(f64, -12.34e10)}); + try testFmt("f64: 9.99996e-40", "f64: {e}", .{@as(f64, 9.999960e-40)}); +} + +test "float.scientific.precision" { + try testFmt("f64: 1.40971e-42", "f64: {e:.5}", .{@as(f64, 1.409706e-42)}); + try testFmt("f64: 1.00000e-09", "f64: {e:.5}", .{@as(f64, @bitCast(f32, @as(u32, 814313563)))}); + try testFmt("f64: 7.81250e-03", "f64: {e:.5}", .{@as(f64, @bitCast(f32, @as(u32, 1006632960)))}); + // libc rounds 1.000005e+05 to 1.00000e+05 but zig does 1.00001e+05. + // In fact, libc doesn't round a lot of 5 cases up when one past the precision point. + try testFmt("f64: 1.00001e+05", "f64: {e:.5}", .{@as(f64, @bitCast(f32, @as(u32, 1203982400)))}); +} + +test "float.special" { + try testFmt("f64: nan", "f64: {}", .{math.nan_f64}); + // negative nan is not defined by IEE 754, + // and ARM thus normalizes it to positive nan + if (builtin.arch != builtin.Arch.arm) { + try testFmt("f64: -nan", "f64: {}", .{-math.nan_f64}); + } + try testFmt("f64: inf", "f64: {}", .{math.inf_f64}); + try testFmt("f64: -inf", "f64: {}", .{-math.inf_f64}); +} + +test "float.decimal" { + try testFmt("f64: 152314000000000000000000000000", "f64: {d}", .{@as(f64, 1.52314e+29)}); + try testFmt("f32: 0", "f32: {d}", .{@as(f32, 0.0)}); + try testFmt("f32: 1.1", "f32: {d:.1}", .{@as(f32, 1.1234)}); + try testFmt("f32: 1234.57", "f32: {d:.2}", .{@as(f32, 1234.567)}); + // -11.1234 is converted to f64 -11.12339... internally (errol3() function takes f64). + // -11.12339... is rounded back up to -11.1234 + try testFmt("f32: -11.1234", "f32: {d:.4}", .{@as(f32, -11.1234)}); + try testFmt("f32: 91.12345", "f32: {d:.5}", .{@as(f32, 91.12345)}); + try testFmt("f64: 91.1234567890", "f64: {d:.10}", .{@as(f64, 91.12345678901235)}); + try testFmt("f64: 0.00000", "f64: {d:.5}", .{@as(f64, 0.0)}); + try testFmt("f64: 6", "f64: {d:.0}", .{@as(f64, 5.700)}); + try testFmt("f64: 10.0", "f64: {d:.1}", .{@as(f64, 9.999)}); + try testFmt("f64: 1.000", "f64: {d:.3}", .{@as(f64, 1.0)}); + try testFmt("f64: 0.00030000", "f64: {d:.8}", .{@as(f64, 0.0003)}); + try testFmt("f64: 0.00000", "f64: {d:.5}", .{@as(f64, 1.40130e-45)}); + try testFmt("f64: 0.00000", "f64: {d:.5}", .{@as(f64, 9.999960e-40)}); +} + +test "float.libc.sanity" { + try testFmt("f64: 0.00001", "f64: {d:.5}", .{@as(f64, @bitCast(f32, @as(u32, 916964781)))}); + try testFmt("f64: 0.00001", "f64: {d:.5}", .{@as(f64, @bitCast(f32, @as(u32, 925353389)))}); + try testFmt("f64: 0.10000", "f64: {d:.5}", .{@as(f64, @bitCast(f32, @as(u32, 1036831278)))}); + try testFmt("f64: 1.00000", "f64: {d:.5}", .{@as(f64, @bitCast(f32, @as(u32, 1065353133)))}); + try testFmt("f64: 10.00000", "f64: {d:.5}", .{@as(f64, @bitCast(f32, @as(u32, 1092616192)))}); + + // libc differences + // + // This is 0.015625 exactly according to gdb. We thus round down, + // however glibc rounds up for some reason. This occurs for all + // floats of the form x.yyyy25 on a precision point. + try testFmt("f64: 0.01563", "f64: {d:.5}", .{@as(f64, @bitCast(f32, @as(u32, 1015021568)))}); + // errol3 rounds to ... 630 but libc rounds to ...632. Grisu3 + // also rounds to 630 so I'm inclined to believe libc is not + // optimal here. + try testFmt("f64: 18014400656965630.00000", "f64: {d:.5}", .{@as(f64, @bitCast(f32, @as(u32, 1518338049)))}); +} + +test "custom" { + const Vec2 = struct { + const SelfType = @This(); + x: f32, + y: f32, + + pub fn format( + self: SelfType, + comptime fmt: []const u8, + options: FormatOptions, + context: var, + comptime Errors: type, + comptime output: fn (@TypeOf(context), []const u8) Errors!void, + ) Errors!void { + if (fmt.len == 0 or comptime std.mem.eql(u8, fmt, "p")) { + return std.fmt.format(context, Errors, output, "({d:.3},{d:.3})", .{ self.x, self.y }); + } else if (comptime std.mem.eql(u8, fmt, "d")) { + return std.fmt.format(context, Errors, output, "{d:.3}x{d:.3}", .{ self.x, self.y }); + } else { + @compileError("Unknown format character: '" ++ fmt ++ "'"); + } + } + }; + + var buf1: [32]u8 = undefined; + var value = Vec2{ + .x = 10.2, + .y = 2.22, + }; + try testFmt("point: (10.200,2.220)\n", "point: {}\n", .{&value}); + try testFmt("dim: 10.200x2.220\n", "dim: {d}\n", .{&value}); + + // same thing but not passing a pointer + try testFmt("point: (10.200,2.220)\n", "point: {}\n", .{value}); + try testFmt("dim: 10.200x2.220\n", "dim: {d}\n", .{value}); +} + +test "struct" { + const S = struct { + a: u32, + b: anyerror, + }; + + const inst = S{ + .a = 456, + .b = error.Unused, + }; + + try testFmt("S{ .a = 456, .b = error.Unused }", "{}", .{inst}); +} + +test "union" { + const TU = union(enum) { + float: f32, + int: u32, + }; + + const UU = union { + float: f32, + int: u32, + }; + + const EU = extern union { + float: f32, + int: u32, + }; + + const tu_inst = TU{ .int = 123 }; + const uu_inst = UU{ .int = 456 }; + const eu_inst = EU{ .float = 321.123 }; + + try testFmt("TU{ .int = 123 }", "{}", .{tu_inst}); + + var buf: [100]u8 = undefined; + const uu_result = try bufPrint(buf[0..], "{}", .{uu_inst}); + std.testing.expect(mem.eql(u8, uu_result[0..3], "UU@")); + + const eu_result = try bufPrint(buf[0..], "{}", .{eu_inst}); + std.testing.expect(mem.eql(u8, uu_result[0..3], "EU@")); +} + +test "enum" { + const E = enum { + One, + Two, + Three, + }; + + const inst = E.Two; + + try testFmt("E.Two", "{}", .{inst}); +} + +test "struct.self-referential" { + const S = struct { + const SelfType = @This(); + a: ?*SelfType, + }; + + var inst = S{ + .a = null, + }; + inst.a = &inst; + + try testFmt("S{ .a = S{ .a = S{ .a = S{ ... } } } }", "{}", .{inst}); +} + +test "struct.zero-size" { + const A = struct { + fn foo() void {} + }; + const B = struct { + a: A, + c: i32, + }; + + const a = A{}; + const b = B{ .a = a, .c = 0 }; + + try testFmt("B{ .a = A{ }, .c = 0 }", "{}", .{b}); +} + +test "bytes.hex" { + const some_bytes = "\xCA\xFE\xBA\xBE"; + try testFmt("lowercase: cafebabe\n", "lowercase: {x}\n", .{some_bytes}); + try testFmt("uppercase: CAFEBABE\n", "uppercase: {X}\n", .{some_bytes}); + //Test Slices + try testFmt("uppercase: CAFE\n", "uppercase: {X}\n", .{some_bytes[0..2]}); + try testFmt("lowercase: babe\n", "lowercase: {x}\n", .{some_bytes[2..]}); + const bytes_with_zeros = "\x00\x0E\xBA\xBE"; + try testFmt("lowercase: 000ebabe\n", "lowercase: {x}\n", .{bytes_with_zeros}); +} + +fn testFmt(expected: []const u8, comptime template: []const u8, args: var) !void { + var buf: [100]u8 = undefined; + const result = try bufPrint(buf[0..], template, args); + if (mem.eql(u8, result, expected)) return; + + std.debug.warn("\n====== expected this output: =========\n", .{}); + std.debug.warn("{}", .{expected}); + std.debug.warn("\n======== instead found this: =========\n", .{}); + std.debug.warn("{}", .{result}); + std.debug.warn("\n======================================\n", .{}); + return error.TestFailed; +} + +pub fn trim(buf: []const u8) []const u8 { + var start: usize = 0; + while (start < buf.len and isWhiteSpace(buf[start])) : (start += 1) {} + + var end: usize = buf.len; + while (true) { + if (end > start) { + const new_end = end - 1; + if (isWhiteSpace(buf[new_end])) { + end = new_end; + continue; + } + } + break; + } + return buf[start..end]; +} + +test "trim" { + std.testing.expect(mem.eql(u8, "abc", trim("\n abc \t"))); + std.testing.expect(mem.eql(u8, "", trim(" "))); + std.testing.expect(mem.eql(u8, "", trim(""))); + std.testing.expect(mem.eql(u8, "abc", trim(" abc"))); + std.testing.expect(mem.eql(u8, "abc", trim("abc "))); +} + +pub fn isWhiteSpace(byte: u8) bool { + return switch (byte) { + ' ', '\t', '\n', '\r' => true, + else => false, + }; +} + +pub fn hexToBytes(out: []u8, input: []const u8) !void { + if (out.len * 2 < input.len) + return error.InvalidLength; + + var in_i: usize = 0; + while (in_i != input.len) : (in_i += 2) { + const hi = try charToDigit(input[in_i], 16); + const lo = try charToDigit(input[in_i + 1], 16); + out[in_i / 2] = (hi << 4) | lo; + } +} + +test "hexToBytes" { + const test_hex_str = "909A312BB12ED1F819B3521AC4C1E896F2160507FFC1C8381E3B07BB16BD1706"; + var pb: [32]u8 = undefined; + try hexToBytes(pb[0..], test_hex_str); + try testFmt(test_hex_str, "{X}", .{pb}); +} + +test "formatIntValue with comptime_int" { + const value: comptime_int = 123456789123456789; + + var buf = std.ArrayList(u8).init(std.testing.allocator); + defer buf.deinit(); + try formatIntValue(value, "", FormatOptions{}, &buf, @TypeOf(std.ArrayList(u8).appendSlice).ReturnType.ErrorSet, std.ArrayList(u8).appendSlice); + std.testing.expect(mem.eql(u8, buf.toSliceConst(), "123456789123456789")); +} + +test "formatType max_depth" { + const Vec2 = struct { + const SelfType = @This(); + x: f32, + y: f32, + + pub fn format( + self: SelfType, + comptime fmt: []const u8, + options: FormatOptions, + context: var, + comptime Errors: type, + comptime output: fn (@TypeOf(context), []const u8) Errors!void, + ) Errors!void { + if (fmt.len == 0) { + return std.fmt.format(context, Errors, output, "({d:.3},{d:.3})", .{ self.x, self.y }); + } else { + @compileError("Unknown format string: '" ++ fmt ++ "'"); + } + } + }; + const E = enum { + One, + Two, + Three, + }; + const TU = union(enum) { + const SelfType = @This(); + float: f32, + int: u32, + ptr: ?*SelfType, + }; + const S = struct { + const SelfType = @This(); + a: ?*SelfType, + tu: TU, + e: E, + vec: Vec2, + }; + + var inst = S{ + .a = null, + .tu = TU{ .ptr = null }, + .e = E.Two, + .vec = Vec2{ .x = 10.2, .y = 2.22 }, + }; + inst.a = &inst; + inst.tu.ptr = &inst.tu; + + var buf0 = std.ArrayList(u8).init(std.testing.allocator); + defer buf0.deinit(); + try formatType(inst, "", FormatOptions{}, &buf0, @TypeOf(std.ArrayList(u8).appendSlice).ReturnType.ErrorSet, std.ArrayList(u8).appendSlice, 0); + std.testing.expect(mem.eql(u8, buf0.toSlice(), "S{ ... }")); + + var buf1 = std.ArrayList(u8).init(std.testing.allocator); + defer buf1.deinit(); + try formatType(inst, "", FormatOptions{}, &buf1, @TypeOf(std.ArrayList(u8).appendSlice).ReturnType.ErrorSet, std.ArrayList(u8).appendSlice, 1); + std.testing.expect(mem.eql(u8, buf1.toSlice(), "S{ .a = S{ ... }, .tu = TU{ ... }, .e = E.Two, .vec = (10.200,2.220) }")); + + var buf2 = std.ArrayList(u8).init(std.testing.allocator); + defer buf2.deinit(); + try formatType(inst, "", FormatOptions{}, &buf2, @TypeOf(std.ArrayList(u8).appendSlice).ReturnType.ErrorSet, std.ArrayList(u8).appendSlice, 2); + std.testing.expect(mem.eql(u8, buf2.toSlice(), "S{ .a = S{ .a = S{ ... }, .tu = TU{ ... }, .e = E.Two, .vec = (10.200,2.220) }, .tu = TU{ .ptr = TU{ ... } }, .e = E.Two, .vec = (10.200,2.220) }")); + + var buf3 = std.ArrayList(u8).init(std.testing.allocator); + defer buf3.deinit(); + try formatType(inst, "", FormatOptions{}, &buf3, @TypeOf(std.ArrayList(u8).appendSlice).ReturnType.ErrorSet, std.ArrayList(u8).appendSlice, 3); + std.testing.expect(mem.eql(u8, buf3.toSlice(), "S{ .a = S{ .a = S{ .a = S{ ... }, .tu = TU{ ... }, .e = E.Two, .vec = (10.200,2.220) }, .tu = TU{ .ptr = TU{ ... } }, .e = E.Two, .vec = (10.200,2.220) }, .tu = TU{ .ptr = TU{ .ptr = TU{ ... } } }, .e = E.Two, .vec = (10.200,2.220) }")); +} + +test "positional" { + try testFmt("2 1 0", "{2} {1} {0}", .{ @as(usize, 0), @as(usize, 1), @as(usize, 2) }); + try testFmt("2 1 0", "{2} {1} {}", .{ @as(usize, 0), @as(usize, 1), @as(usize, 2) }); + try testFmt("0 0", "{0} {0}", .{@as(usize, 0)}); + try testFmt("0 1", "{} {1}", .{ @as(usize, 0), @as(usize, 1) }); + try testFmt("1 0 0 1", "{1} {} {0} {}", .{ @as(usize, 0), @as(usize, 1) }); +} + +test "positional with specifier" { + try testFmt("10.0", "{0d:.1}", .{@as(f64, 9.999)}); +} + +test "positional/alignment/width/precision" { + try testFmt("10.0", "{0d: >3.1}", .{@as(f64, 9.999)}); +} + +test "vector" { + // https://github.com/ziglang/zig/issues/3317 + if (builtin.arch == .mipsel) return error.SkipZigTest; + + const vbool: @Vector(4, bool) = [_]bool{ true, false, true, false }; + const vi64: @Vector(4, i64) = [_]i64{ -2, -1, 0, 1 }; + const vu64: @Vector(4, u64) = [_]u64{ 1000, 2000, 3000, 4000 }; + + try testFmt("{ true, false, true, false }", "{}", .{vbool}); + try testFmt("{ -2, -1, 0, 1 }", "{}", .{vi64}); + try testFmt("{ - 2, - 1, + 0, + 1 }", "{d:5}", .{vi64}); + try testFmt("{ 1000, 2000, 3000, 4000 }", "{}", .{vu64}); + try testFmt("{ 3e8, 7d0, bb8, fa0 }", "{x}", .{vu64}); + try testFmt("{ 1kB, 2kB, 3kB, 4kB }", "{B}", .{vu64}); + try testFmt("{ 1000B, 1.953125KiB, 2.9296875KiB, 3.90625KiB }", "{Bi}", .{vu64}); +} + +test "enum-literal" { + try testFmt(".hello_world", "{}", .{.hello_world}); +} diff --git a/lib/std/std.zig b/lib/std/std.zig index 9277370ca6..b7fe709c7c 100644 --- a/lib/std/std.zig +++ b/lib/std/std.zig @@ -38,6 +38,7 @@ pub const elf = @import("elf.zig"); pub const event = @import("event.zig"); pub const fifo = @import("fifo.zig"); pub const fmt = @import("fmt.zig"); +pub const fmtstream = @import("fmtstream.zig"); pub const fs = @import("fs.zig"); pub const hash = @import("hash.zig"); pub const hash_map = @import("hash_map.zig");