Rollup merge of #130034 - alexcrichton:fix-some-wasm-component-ld-comments, r=onur-ozkan

 Fix enabling wasm-component-ld to match other tools

It was [pointed out recently][comment] that enabling `wasm-component-ld` as a host tool is different from other host tools. This commit refactors the logic to match by deduplicating selection of when to build other tools and then using the same logic for `wasm-component-ld`.

While here I also fixed a typo pointed out in https://github.com/rust-lang/rust/pull/126967#pullrequestreview-2285267534

[comment]: https://github.com/rust-lang/rust/pull/127866#issuecomment-2333434720

5 files changed, 19 insertions, 44 deletions

diff --git a/src/bootstrap/src/core/build_steps/compile.rs b/src/bootstrap/src/core/build_steps/compile.rs
index 1936c91ef83..102c9fd2554 100644
--- a/src/bootstrap/src/core/build_steps/compile.rs
+++ b/src/bootstrap/src/core/build_steps/compile.rs
@@ -1912,7 +1912,7 @@ impl Step for Assemble {
         // delegates to the `rust-lld` binary for linking and then runs
         // logic to create the final binary. This is used by the
         // `wasm32-wasip2` target of Rust.
-        if builder.build_wasm_component_ld() {
+        if builder.tool_enabled("wasm-component-ld") {
             let wasm_component_ld_exe =
                 builder.ensure(crate::core::build_steps::tool::WasmComponentLd {
                     compiler: build_compiler,
diff --git a/src/bootstrap/src/core/build_steps/dist.rs b/src/bootstrap/src/core/build_steps/dist.rs
index 4957de2e1b7..ccb5656d671 100644
--- a/src/bootstrap/src/core/build_steps/dist.rs
+++ b/src/bootstrap/src/core/build_steps/dist.rs
@@ -473,7 +473,7 @@ impl Step for Rustc {
                     );
                 }
             }
-            if builder.build_wasm_component_ld() {
+            if builder.tool_enabled("wasm-component-ld") {
                 let src_dir = builder.sysroot_libdir(compiler, host).parent().unwrap().join("bin");
                 let ld = exe("wasm-component-ld", compiler.host);
                 builder.copy_link(&src_dir.join(&ld), &dst_dir.join(&ld));
diff --git a/src/bootstrap/src/core/build_steps/tool.rs b/src/bootstrap/src/core/build_steps/tool.rs
index 3a1eb43b801..3c2d791c209 100644
--- a/src/bootstrap/src/core/build_steps/tool.rs
+++ b/src/bootstrap/src/core/build_steps/tool.rs
@@ -693,14 +693,7 @@ impl Step for Cargo {
 
     fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
         let builder = run.builder;
-        run.path("src/tools/cargo").default_condition(
-            builder.config.extended
-                && builder.config.tools.as_ref().map_or(
-                    true,
-                    // If `tools` is set, search list for this tool.
-                    |tools| tools.iter().any(|tool| tool == "cargo"),
-                ),
-        )
+        run.path("src/tools/cargo").default_condition(builder.tool_enabled("cargo"))
     }
 
     fn make_run(run: RunConfig<'_>) {
@@ -772,14 +765,7 @@ impl Step for RustAnalyzer {
 
     fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
         let builder = run.builder;
-        run.path("src/tools/rust-analyzer").default_condition(
-            builder.config.extended
-                && builder
-                    .config
-                    .tools
-                    .as_ref()
-                    .map_or(true, |tools| tools.iter().any(|tool| tool == "rust-analyzer")),
-        )
+        run.path("src/tools/rust-analyzer").default_condition(builder.tool_enabled("rust-analyzer"))
     }
 
     fn make_run(run: RunConfig<'_>) {
@@ -821,12 +807,8 @@ impl Step for RustAnalyzerProcMacroSrv {
         run.path("src/tools/rust-analyzer")
             .path("src/tools/rust-analyzer/crates/proc-macro-srv-cli")
             .default_condition(
-                builder.config.extended
-                    && builder.config.tools.as_ref().map_or(true, |tools| {
-                        tools.iter().any(|tool| {
-                            tool == "rust-analyzer" || tool == "rust-analyzer-proc-macro-srv"
-                        })
-                    }),
+                builder.tool_enabled("rust-analyzer")
+                    || builder.tool_enabled("rust-analyzer-proc-macro-srv"),
             )
     }
 
@@ -874,16 +856,8 @@ impl Step for LlvmBitcodeLinker {
 
     fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
         let builder = run.builder;
-        run.path("src/tools/llvm-bitcode-linker").default_condition(
-            builder.config.extended
-                && builder
-                    .config
-                    .tools
-                    .as_ref()
-                    .map_or(builder.build.unstable_features(), |tools| {
-                        tools.iter().any(|tool| tool == "llvm-bitcode-linker")
-                    }),
-        )
+        run.path("src/tools/llvm-bitcode-linker")
+            .default_condition(builder.tool_enabled("llvm-bitcode-linker"))
     }
 
     fn make_run(run: RunConfig<'_>) {
diff --git a/src/bootstrap/src/lib.rs b/src/bootstrap/src/lib.rs
index c76ce340956..780024e307e 100644
--- a/src/bootstrap/src/lib.rs
+++ b/src/bootstrap/src/lib.rs
@@ -1407,16 +1407,17 @@ Executed at: {executed_at}"#,
         None
     }
 
-    /// Returns whether it's requested that `wasm-component-ld` is built as part
-    /// of the sysroot. This is done either with the `extended` key in
-    /// `config.toml` or with the `tools` set.
-    fn build_wasm_component_ld(&self) -> bool {
-        if self.config.extended {
-            return true;
+    /// Returns whether the specified tool is configured as part of this build.
+    ///
+    /// This requires that both the `extended` key is set and the `tools` key is
+    /// either unset or specifically contains the specified tool.
+    fn tool_enabled(&self, tool: &str) -> bool {
+        if !self.config.extended {
+            return false;
         }
         match &self.config.tools {
-            Some(set) => set.contains("wasm-component-ld"),
-            None => false,
+            Some(set) => set.contains(tool),
+            None => true,
         }
     }
 
diff --git a/src/tools/wasm-component-ld/README.md b/src/tools/wasm-component-ld/README.md
index 54608a2dea1..b51de9a9dce 100644
--- a/src/tools/wasm-component-ld/README.md
+++ b/src/tools/wasm-component-ld/README.md
@@ -1,7 +1,7 @@
 # `wasm-component-ld`
 
-This wrapper is a wrapper around the [`wasm-component-ld`] crates.io crate. That
-crate. That crate is itself a thin wrapper around two pieces:
+This wrapper is a wrapper around the [`wasm-component-ld`] crates.io crate.
+That crate is itself a thin wrapper around two pieces:
 
 * `wasm-ld` - the LLVM-based linker distributed as part of LLD and packaged in
   Rust as `rust-lld`.