Make legacy UI test directive detection more robust

Author: jieyouxu

src/tools/compiletest/src/header.rs

@@ -653,6 +653,124 @@ fn iter_header<R: Read>(
     iter_header_extra(mode, poisoned, testfile, rdr, &[], it)
 }
 
+/// This is generated by collecting directives from ui tests and then extracting their directive
+/// names. This is **not** an exhaustive list of all possible directives. Instead, this is a
+/// best-effort approximation for diagnostics.
+const DIAGNOSTICS_DIRECTIVE_NAMES: &[&str] = &[
+    "aux-build",
+    "aux-crate",
+    "build-fail",
+    "build-pass",
+    "check-fail",
+    "check-pass",
+    "check-run-results",
+    "check-stdout",
+    "compile-flags",
+    "dont-check-compiler-stderr",
+    "dont-check-compiler-stdout",
+    "dont-check-failure-status",
+    "edition",
+    "error-pattern",
+    "exec-env",
+    "failure-status",
+    "forbid-output",
+    "force-host",
+    "ignore-32bit",
+    "ignore-64bit",
+    "ignore-aarch64",
+    "ignore-aarch64-unknown-linux-gnu",
+    "ignore-android",
+    "ignore-arm",
+    "ignore-compare-mode-next-solver",
+    "ignore-compare-mode-polonius",
+    "ignore-cross-compile",
+    "ignore-debug",
+    "ignore-emscripten",
+    "ignore-endian-big",
+    "ignore-freebsd",
+    "ignore-fuchsia",
+    "ignore-gnu",
+    "ignore-haiku",
+    "ignore-horizon",
+    "ignore-i686-pc-windows-msvc",
+    "ignore-ios",
+    "ignore-llvm-version",
+    "ignore-macos",
+    "ignore-msvc",
+    "ignore-musl",
+    "ignore-netbsd",
+    "ignore-nightly",
+    "ignore-nto",
+    "ignore-nvptx64",
+    "ignore-openbsd",
+    "ignore-pass",
+    "ignore-sgx",
+    "ignore-spirv",
+    "ignore-test",
+    "ignore-thumbv8m.base-none-eabi",
+    "ignore-thumbv8m.main-none-eabi",
+    "ignore-uwp",
+    "ignore-vxworks",
+    "ignore-wasm",
+    "ignore-wasm32",
+    "ignore-wasm32-bare",
+    "ignore-windows",
+    "ignore-x86",
+    "incremental",
+    "known-bug",
+    "min-llvm-version",
+    "needs-asm-support",
+    "needs-dlltool",
+    "needs-dynamic-linking",
+    "needs-llvm-components",
+    "needs-profiler-support",
+    "needs-relocation-model-pic",
+    "needs-run-enabled",
+    "needs-sanitizer-address",
+    "needs-sanitizer-cfi",
+    "needs-sanitizer-hwaddress",
+    "needs-sanitizer-leak",
+    "needs-sanitizer-memory",
+    "needs-sanitizer-support",
+    "needs-sanitizer-thread",
+    "needs-unwind",
+    "needs-xray",
+    "no-prefer-dynamic",
+    "normalize-stderr-32bit",
+    "normalize-stderr-64bit",
+    "normalize-stderr-test",
+    "normalize-stdout-test",
+    "only-32bit",
+    "only-64bit",
+    "only-aarch64",
+    "only-gnu",
+    "only-i686-pc-windows-msvc",
+    "only-linux",
+    "only-macos",
+    "only-msvc",
+    "only-nightly",
+    "only-wasm32",
+    "only-windows",
+    "only-x86",
+    "only-x86_64",
+    "only-x86_64-pc-windows-msvc",
+    "only-x86_64-unknown-linux-gnu",
+    "pp-exact",
+    "pretty-expanded",
+    "regex-error-pattern",
+    "remap-src-base",
+    "revisions",
+    "run-fail",
+    "run-flags",
+    "run-pass",
+    "run-rustfix",
+    "rustc-env",
+    "rustfix-only-machine-applicable",
+    "should-fail",
+    "stderr-per-bitwidth",
+    "unset-rustc-env",
+];
+
 fn iter_header_extra(
     mode: Mode,
     poisoned: &mut bool,
@@ -681,7 +799,7 @@ fn iter_header_extra(
     let mut ln = String::new();
     let mut line_number = 0;
 
-    let revision_magic_comment = Regex::new("//(\\[.*\\])~.*").unwrap();
+    let revision_magic_comment = Regex::new("//(\\[.*\\])?~.*").unwrap();
 
     loop {
         line_number += 1;
@@ -701,20 +819,33 @@ fn iter_header_extra(
         // First try to accept `ui_test` style comments
         } else if let Some((lncfg, ln)) = line_directive(comment, ln) {
             it(lncfg, orig_ln, ln, line_number);
-        } else if mode == Mode::Ui
-            && !revision_magic_comment.is_match(ln)
-            && matches!(line_directive("//", ln), Some((Some(_), _)))
-        {
-            // We have a comment that's *successfully* parsed as an legacy-style directive.
-            // We emit an error here to warn the user.
-            *poisoned = true;
-            eprintln!(
-                "error: detected legacy-style directives in ui test: {}:{}, please use `ui_test`-style directives `//@` instead:{:#?}",
-                testfile.display(),
-                line_number,
-                line_directive("//", ln),
-            );
-            return;
+        } else if mode == Mode::Ui && !revision_magic_comment.is_match(ln) {
+            let Some((_, rest)) = line_directive("//", ln) else {
+                continue;
+            };
+
+            if rest.trim_start().starts_with(':') {
+                // This is likely a markdown link:
+                // `[link_name]: https://example.org`
+                continue;
+            }
+
+            let rest = rest.trim_start();
+
+            for candidate in DIAGNOSTICS_DIRECTIVE_NAMES.iter() {
+                if rest.starts_with(candidate) {
+                    // We have a comment that's *successfully* parsed as an legacy-style directive.
+                    // We emit an error here to warn the user.
+                    *poisoned = true;
+                    eprintln!(
+                        "error: detected legacy-style directives in ui test: {}:{}, please use `ui_test`-style directives `//@` instead:{:#?}",
+                        testfile.display(),
+                        line_number,
+                        line_directive("//", ln),
+                    );
+                    return;
+                }
+            }
         }
     }
 }