[3.14] gh-142278: Add granular change detection for platforms in CI (GH-142350) (#142537)

Co-authored-by: Hugo van Kemenade <1324225+hugovk@users.noreply.github.com>

Tools/build/compute-changes.py

@@ -45,12 +45,22 @@
 SUFFIXES_C_OR_CPP = frozenset({".c", ".h", ".cpp"})
 SUFFIXES_DOCUMENTATION = frozenset({".rst", ".md"})
 
+ANDROID_DIRS = frozenset({"Android"})
+IOS_DIRS = frozenset({"Apple", "iOS"})
+MACOS_DIRS = frozenset({"Mac"})
+WASI_DIRS = frozenset({Path("Tools", "wasm")})
+
 
 @dataclass(kw_only=True, slots=True)
 class Outputs:
+    run_android: bool = False
     run_ci_fuzz: bool = False
     run_docs: bool = False
+    run_ios: bool = False
+    run_macos: bool = False
     run_tests: bool = False
+    run_ubuntu: bool = False
+    run_wasi: bool = False
     run_windows_msi: bool = False
     run_windows_tests: bool = False
 
@@ -63,7 +73,15 @@ def compute_changes() -> None:
         outputs = process_changed_files(files)
     else:
         # Otherwise, just run the tests
-        outputs = Outputs(run_tests=True, run_windows_tests=True)
+        outputs = Outputs(
+            run_android=True,
+            run_ios=True,
+            run_macos=True,
+            run_tests=True,
+            run_ubuntu=True,
+            run_wasi=True,
+            run_windows_tests=True,
+        )
     outputs = process_target_branch(outputs, target_branch)
 
     if outputs.run_tests:
@@ -111,6 +129,21 @@ def get_changed_files(
     return frozenset(map(Path, filter(None, map(str.strip, changed_files))))
 
 
+def get_file_platform(file: Path) -> str | None:
+    if not file.parts:
+        return None
+    first_part = file.parts[0]
+    if first_part in MACOS_DIRS:
+        return "macos"
+    if first_part in IOS_DIRS:
+        return "ios"
+    if first_part in ANDROID_DIRS:
+        return "android"
+    if len(file.parts) >= 2 and Path(*file.parts[:2]) in WASI_DIRS: # Tools/wasm/
+        return "wasi"
+    return None
+
+
 def process_changed_files(changed_files: Set[Path]) -> Outputs:
     run_tests = False
     run_ci_fuzz = False
@@ -118,6 +151,9 @@ def process_changed_files(changed_files: Set[Path]) -> Outputs:
     run_windows_tests = False
     run_windows_msi = False
 
+    platforms_changed = set()
+    has_platform_specific_change = True
+
     for file in changed_files:
         # Documentation files
         doc_or_misc = file.parts[0] in {"Doc", "Misc"}
@@ -126,10 +162,15 @@ def process_changed_files(changed_files: Set[Path]) -> Outputs:
         if file.parent == GITHUB_WORKFLOWS_PATH:
             if file.name == "build.yml":
                 run_tests = run_ci_fuzz = True
+                has_platform_specific_change = False
             if file.name == "reusable-docs.yml":
                 run_docs = True
             if file.name == "reusable-windows-msi.yml":
                 run_windows_msi = True
+            if file.name == "reusable-macos.yml":
+                platforms_changed.add("macos")
+            if file.name == "reusable-wasi.yml":
+                platforms_changed.add("wasi")
 
         if not (
             doc_file
@@ -138,8 +179,13 @@ def process_changed_files(changed_files: Set[Path]) -> Outputs:
         ):
             run_tests = True
 
-            if file not in UNIX_BUILD_SYSTEM_FILE_NAMES:
-                run_windows_tests = True
+            platform = get_file_platform(file)
+            if platform is not None:
+                platforms_changed.add(platform)
+            else:
+                has_platform_specific_change = False
+                if file not in UNIX_BUILD_SYSTEM_FILE_NAMES:
+                    run_windows_tests = True
 
         # The fuzz tests are pretty slow so they are executed only for PRs
         # changing relevant files.
@@ -159,12 +205,38 @@ def process_changed_files(changed_files: Set[Path]) -> Outputs:
         if file.parts[:2] == ("Tools", "msi"):
             run_windows_msi = True
 
+    # Check which platform specific tests to run
+    if run_tests:
+        if not has_platform_specific_change or not platforms_changed:
+            run_android = True
+            run_ios = True
+            run_macos = True
+            run_ubuntu = True
+            run_wasi = True
+        else:
+            run_android = "android" in platforms_changed
+            run_ios = "ios" in platforms_changed
+            run_macos = "macos" in platforms_changed
+            run_ubuntu = False
+            run_wasi = "wasi" in platforms_changed
+    else:
+        run_android = False
+        run_ios = False
+        run_macos = False
+        run_ubuntu = False
+        run_wasi = False
+
     return Outputs(
+        run_android=run_android,
         run_ci_fuzz=run_ci_fuzz,
         run_docs=run_docs,
+        run_ios=run_ios,
+        run_macos=run_macos,
         run_tests=run_tests,
-        run_windows_tests=run_windows_tests,
+        run_ubuntu=run_ubuntu,
+        run_wasi=run_wasi,
         run_windows_msi=run_windows_msi,
+        run_windows_tests=run_windows_tests,
     )
 
 
@@ -191,11 +263,16 @@ def write_github_output(outputs: Outputs) -> None:
         return
 
     with open(os.environ["GITHUB_OUTPUT"], "a", encoding="utf-8") as f:
+        f.write(f"run-android={bool_lower(outputs.run_android)}\n")
         f.write(f"run-ci-fuzz={bool_lower(outputs.run_ci_fuzz)}\n")
         f.write(f"run-docs={bool_lower(outputs.run_docs)}\n")
+        f.write(f"run-ios={bool_lower(outputs.run_ios)}\n")
+        f.write(f"run-macos={bool_lower(outputs.run_macos)}\n")
         f.write(f"run-tests={bool_lower(outputs.run_tests)}\n")
-        f.write(f"run-windows-tests={bool_lower(outputs.run_windows_tests)}\n")
+        f.write(f"run-ubuntu={bool_lower(outputs.run_ubuntu)}\n")
+        f.write(f"run-wasi={bool_lower(outputs.run_wasi)}\n")
         f.write(f"run-windows-msi={bool_lower(outputs.run_windows_msi)}\n")
+        f.write(f"run-windows-tests={bool_lower(outputs.run_windows_tests)}\n")
 
 
 def bool_lower(value: bool, /) -> str: