std.Build.Step.WriteFile: extract UpdateSourceFiles

This has been planned for quite some time; this commit finally does it.

Also implements file system watching integration in the make()
implementation for UpdateSourceFiles and fixes the reporting of step
caching for both.

WriteFile does not yet have file system watching integration.

1 files changed, 1 insertions, 1 deletions

diff --git a/build.zig b/build.zig
index 0f0d7d4d67..a364982ce9 100644
--- a/build.zig
+++ b/build.zig
@@ -595,7 +595,7 @@ fn addWasiUpdateStep(b: *std.Build, version: [:0]const u8) !void {
     run_opt.addArg("-o");
     run_opt.addFileArg(b.path("stage1/zig1.wasm"));
 
-    const copy_zig_h = b.addWriteFiles();
+    const copy_zig_h = b.addUpdateSourceFiles();
     copy_zig_h.addCopyFileToSource(b.path("lib/zig.h"), "stage1/zig.h");
 
     const update_zig1_step = b.step("update-zig1", "Update stage1/zig1.wasm");