From 45713ec8ab21f81291bc14e2725730dac26d5137 Mon Sep 17 00:00:00 2001 From: Manlio Perillo Date: Mon, 3 Apr 2023 11:06:39 +0200 Subject: [PATCH] build: restore support for Zig 0.6.0 The version check for Zig 0.6.0 was incorrect since commit 971ab7f (Use a zig build script to run ziglings). Move compatibility support to a separate file, in order to simplify build.zig. In case of incompatible version, exit with code 3 instead of 0, in order to detect the case of failure in a test (to be implemented). Remove the use of comptime when checking compatibility at the start of the build function, since it is not necessary. Closes #210. --- build.zig | 58 ++++++++------------------------------------ src/compat.zig | 65 ++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 75 insertions(+), 48 deletions(-) create mode 100644 src/compat.zig diff --git a/build.zig b/build.zig index 035f0bb..a315a51 100644 --- a/build.zig +++ b/build.zig @@ -1,15 +1,13 @@ const std = @import("std"); const builtin = @import("builtin"); -const Builder = std.build.Builder; -const Step = std.build.Step; +const compat = @import("src/compat.zig"); + +const Build = compat.Build; +const Step = compat.build.Step; + const assert = std.debug.assert; const print = std.debug.print; -// When changing this version, be sure to also update README.md in two places: -// 1) Getting Started -// 2) Version Changes -const needed_version = std.SemanticVersion.parse("0.11.0-dev.2157") catch unreachable; - const Exercise = struct { /// main_file must have the format key_name.zig. /// The key will be used as a shorthand to build @@ -493,44 +491,8 @@ const exercises = [_]Exercise{ }, }; -/// Check the zig version to make sure it can compile the examples properly. -/// This will compile with Zig 0.6.0 and later. -fn checkVersion() bool { - if (!@hasDecl(builtin, "zig_version")) { - return false; - } - - const version = builtin.zig_version; - const order = version.order(needed_version); - return order != .lt; -} - -pub fn build(b: *Builder) !void { - // Use a comptime branch for the version check. - // If this fails, code after this block is not compiled. - // It is parsed though, so versions of zig from before 0.6.0 - // cannot do the version check and will just fail to compile. - // We could fix this by moving the ziglings code to a separate file, - // but 0.5.0 was a long time ago, it is unlikely that anyone who - // attempts these exercises is still using it. - if (comptime !checkVersion()) { - // very old versions of Zig used warn instead of print. - const stderrPrintFn = if (@hasDecl(std.debug, "print")) std.debug.print else std.debug.warn; - stderrPrintFn( - \\ERROR: Sorry, it looks like your version of zig is too old. :-( - \\ - \\Ziglings requires development build - \\ - \\ {} - \\ - \\or higher. Please download a development ("master") build from - \\ - \\ https://ziglang.org/download/ - \\ - \\ - , .{needed_version}); - std.os.exit(0); - } +pub fn build(b: *Build) !void { + if (!compat.is_compatible) compat.die(); use_color_escapes = false; if (std.io.getStdErr().supportsAnsiEscapeCodes()) { @@ -629,10 +591,10 @@ var reset_text: []const u8 = ""; const ZiglingStep = struct { step: Step, exercise: Exercise, - builder: *Builder, + builder: *Build, use_healed: bool, - pub fn create(builder: *Builder, exercise: Exercise, use_healed: bool) *@This() { + pub fn create(builder: *Build, exercise: Exercise, use_healed: bool) *@This() { const self = builder.allocator.create(@This()) catch unreachable; self.* = .{ .step = Step.init(Step.Options{ .id = .custom, .name = exercise.main_file, .owner = builder, .makeFn = make }), @@ -813,7 +775,7 @@ const PrintStep = struct { message: []const u8, file: std.fs.File, - pub fn create(owner: *std.Build, message: []const u8, file: std.fs.File) *PrintStep { + pub fn create(owner: *Build, message: []const u8, file: std.fs.File) *PrintStep { const self = owner.allocator.create(PrintStep) catch @panic("OOM"); self.* = .{ .step = Step.init(.{ diff --git a/src/compat.zig b/src/compat.zig new file mode 100644 index 0000000..34dfc76 --- /dev/null +++ b/src/compat.zig @@ -0,0 +1,65 @@ +/// Compatibility support for very old versions of Zig and recent versions before +/// commit efa25e7d5 (Merge pull request #14498 from ziglang/zig-build-api). +/// +/// Versions of Zig from before 0.6.0 cannot do the version check and will just +/// fail to compile, but 0.5.0 was a long time ago, it is unlikely that anyone +/// who attempts these exercises is still using it. +const std = @import("std"); +const builtin = @import("builtin"); + +const debug = std.debug; + +// Very old versions of Zig used warn instead of print. +const print = if (@hasDecl(debug, "print")) debug.print else debug.warn; + +// When changing this version, be sure to also update README.md in two places: +// 1) Getting Started +// 2) Version Changes +const needed_version_str = "0.11.0-dev.2157"; + +fn isCompatible() bool { + if (!@hasDecl(builtin, "zig_version") or !@hasDecl(std, "SemanticVersion")) { + return false; + } + + const needed_version = std.SemanticVersion.parse(needed_version_str) catch unreachable; + const version = builtin.zig_version; + const order = version.order(needed_version); + + return order != .lt; +} + +pub fn die() noreturn { + const error_message = + \\ERROR: Sorry, it looks like your version of zig is too old. :-( + \\ + \\Ziglings requires development build + \\ + \\ {s} + \\ + \\or higher. Please download a development ("master") build from + \\ + \\ https://ziglang.org/download/ + \\ + \\ + ; + + print(error_message, .{needed_version_str}); + + // Use exit code 2, to differentiate from a normal Zig compiler error. + std.os.exit(2); +} + +// A separate function is required because very old versions of Zig doesn't +// support labeled block expressions. +pub const is_compatible: bool = isCompatible(); + +/// This is the type to be used only for the build function definition, since +/// the type must be compatible with the build runner. +/// +/// Don't use std.Build.Builder, since it is deprecated and may be removed in +/// future. +pub const Build = if (is_compatible) std.Build else std.build.Builder; + +/// This is the type to be used for accessing the build namespace. +pub const build = if (is_compatible) std.Build else std.build;