From 57d2129baeabbf799abbe58a0c90d035b3134d52 Mon Sep 17 00:00:00 2001
From: chloe caruso <git@paperclover.net>
Date: Tue, 23 Jul 2024 04:56:31 -0700
Subject: [PATCH] add automatic version detection from changelog

---
 CHANGELOG.md         |  2 ++
 build.zig            | 22 ++++++++++++++++++----
 src/core/js/Link.zig | 14 +++++++++-----
 src/core/mod.zig     |  3 +++
 4 files changed, 32 insertions(+), 9 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 1385b355b836d05ea471ce9a62cda2797578a651..d839acacc037994a584756874aaeb0b6a4883fcd 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,5 @@
+## 0.1.5
+
 ## 0.1.4
 
 - feat: implement basic struct types (#42)
diff --git a/build.zig b/build.zig
index 517d5d22517572c1750f5a7c4568e2f869ef3e86..1d89a00731183659d272831ae7928c5871cf622a 100644
--- a/build.zig
+++ b/build.zig
@@ -3,7 +3,7 @@ const Build = std.Build;
 const Target = std.Target;
 const OsVersion = Target.Query.OsVersion;
 
-pub fn build(b: *std.Build) void {
+pub fn build(b: *std.Build) !void {
     b.reference_trace = 20;
 
     const native_target = b.resolveTargetQuery(.{});
@@ -40,8 +40,20 @@ pub fn build(b: *std.Build) void {
         "Experiment with the Zig self-hosted backends",
     ) orelse false;
 
-    const native_debug = buildWithTarget(b, native_target, .Debug, .none, no_llvm);
-    const main = buildWithTarget(b, target, optimize, tracing, no_llvm);
+    const version = version: {
+        const text = try b.build_root.handle.readFileAlloc(
+            b.graph.arena,
+            "CHANGELOG.md",
+            std.math.maxInt(usize),
+        );
+        const first_header = std.mem.indexOf(u8, text, "## ") orelse unreachable;
+        var tokenizer = std.mem.tokenizeAny(u8, text[first_header + 2 ..], " \t\n");
+        const version_text = tokenizer.next() orelse unreachable;
+        break :version std.SemanticVersion.parse(version_text) catch unreachable;
+    };
+
+    const native_debug = buildWithTarget(b, native_target, .Debug, .none, version, no_llvm);
+    const main = buildWithTarget(b, target, optimize, tracing, version, no_llvm);
 
     b.installArtifact(main.compiler);
 
@@ -133,7 +145,7 @@ pub fn build(b: *std.Build) void {
             },
         ) catch @panic("OOM");
 
-        const artifacts = buildWithTarget(b, cross_target, .ReleaseSafe, .none, no_llvm);
+        const artifacts = buildWithTarget(b, cross_target, .ReleaseSafe, .none, version, no_llvm);
 
         inline for (.{
             .{ artifacts.compiler, "compiler" },
@@ -173,6 +185,7 @@ fn buildWithTarget(
     target: Build.ResolvedTarget,
     optimize: std.builtin.OptimizeMode,
     tracing: TracingMode,
+    version: std.SemanticVersion,
     no_llvm: bool,
 ) Artifacts {
     const dep_opts = .{ .target = target, .optimize = optimize };
@@ -185,6 +198,7 @@ fn buildWithTarget(
 
     // Options
     const opts = b.addOptions();
+    opts.addOption(std.SemanticVersion, "version", version);
     opts.addOption([]const u8, "tracing", @tagName(tracing));
     const opts_mod = opts.createModule();
 
diff --git a/src/core/js/Link.zig b/src/core/js/Link.zig
index 05a565491a6436eeab9e4c67060e66f8a0e2d81a..be43e842e1deb0c2d507dfc42662b09c6b9130c6 100644
--- a/src/core/js/Link.zig
+++ b/src/core/js/Link.zig
@@ -70,7 +70,10 @@ pub fn linkJsCode(link: *Link, entry_decl: Decl.Index, writer: Writer) !void {
         try link.decls.putNoClobber(link.comp.gpa, value, @enumFromInt(gop.index));
     }
 
-    try writer.print("// Language Compiler v0.1.4. Alpha quality software.\n", .{});
+    try writer.writeAll(std.fmt.comptimePrint(
+        "// Language Compiler v{}. Alpha quality software.\n",
+        .{core.version},
+    ));
 
     if (root_function.nodes.len > 1) {
         // 2. Print every function decl
@@ -843,14 +846,15 @@ const Wyhash = std.hash.Wyhash;
 const log = std.log.scoped(.js_link);
 const Writer = std.io.AnyWriter;
 
-const Comp = @import("../Comp.zig");
+const core = @import("../mod.zig");
+const Comp = core.Comp;
 const Decl = Comp.Decl;
 
-const Js = @import("Js.zig");
-const Tree = @import("Tree.zig");
+const Js = core.Js;
+const Tree = Js.Tree;
 const Node = Tree.Node;
 
-const InternPool = @import("../InternPool.zig");
+const InternPool = core.InternPool;
 const String = InternPool.String;
 
 const tracer = @import("tracer");
diff --git a/src/core/mod.zig b/src/core/mod.zig
index 5dc23f406d46cd95b8b865846bd53e1bec40c756..cc3a1e17802775e1f7583fd91c2e5237571d1db1 100644
--- a/src/core/mod.zig
+++ b/src/core/mod.zig
@@ -48,6 +48,9 @@ pub const unicode_props = @import("unicode_props.zig");
 // The rest of this file is utility functions, which are not specific to any of
 // the above namespaces. Remember Zig discourages namespaces like `utils`
 
+/// Language SDK version according to the latest entry in `CHANGELOG.md`
+pub const version = @import("build_options").version;
+
 /// This is an alternative to `std.debug.assert`, where you want to print some
 /// debug info instead of "reached unreachable code". Usage is as follows:
 ///
-- 
2.54.0