bp2build: fix exclude_srcs in subpackages.

In a non-top level Android.bp file, exclude_srcs was not working at all
due to a bug in expandSrcsForBazel. GlobFiles was expanding a glob
relative to root, but the expandedExcludes list was relative to the
module dir, causing the glob function to not consider the
expandedExcludes list at all.

Add tests to demonstrate that this is working now.

Test: TH
Bug: 186388919
Change-Id: Ice8254231d085b39126e91b823a09ec328ee0ae0

android/bazel_paths.go

@@ -243,6 +243,14 @@ func expandSrcsForBazel(ctx BazelConversionPathContext, paths, expandedExcludes
 	labels := bazel.LabelList{
 		Includes: []bazel.Label{},
 	}
+
+	// expandedExcludes contain module-dir relative paths, but root-relative paths
+	// are needed for GlobFiles later.
+	var rootRelativeExpandedExcludes []string
+	for _, e := range expandedExcludes {
+		rootRelativeExpandedExcludes = append(rootRelativeExpandedExcludes, filepath.Join(ctx.ModuleDir(), e))
+	}
+
 	for _, p := range paths {
 		if m, tag := SrcIsModuleWithTag(p); m != "" {
 			l := getOtherModuleLabel(ctx, m, tag)
@@ -253,7 +261,10 @@ func expandSrcsForBazel(ctx BazelConversionPathContext, paths, expandedExcludes
 		} else {
 			var expandedPaths []bazel.Label
 			if pathtools.IsGlob(p) {
-				globbedPaths := GlobFiles(ctx, pathForModuleSrc(ctx, p).String(), expandedExcludes)
+				// e.g. turn "math/*.c" in
+				// external/arm-optimized-routines to external/arm-optimized-routines/math/*.c
+				rootRelativeGlobPath := pathForModuleSrc(ctx, p).String()
+				globbedPaths := GlobFiles(ctx, rootRelativeGlobPath, rootRelativeExpandedExcludes)
 				globbedPaths = PathsWithModuleSrcSubDir(ctx, globbedPaths, "")
 				for _, path := range globbedPaths {
 					s := path.Rel()

bp2build/build_conversion_test.go

@@ -1512,3 +1512,126 @@ filegroup {
 		}
 	}
 }
+
+func TestGlobExcludeSrcs(t *testing.T) {
+	testCases := []struct {
+		description                        string
+		moduleTypeUnderTest                string
+		moduleTypeUnderTestFactory         android.ModuleFactory
+		moduleTypeUnderTestBp2BuildMutator func(android.TopDownMutatorContext)
+		bp                                 string
+		expectedBazelTargets               []string
+		fs                                 map[string]string
+		dir                                string
+	}{
+		{
+			description:                        "filegroup top level exclude_srcs",
+			moduleTypeUnderTest:                "filegroup",
+			moduleTypeUnderTestFactory:         android.FileGroupFactory,
+			moduleTypeUnderTestBp2BuildMutator: android.FilegroupBp2Build,
+			bp: `filegroup {
+    name: "fg_foo",
+    srcs: ["**/*.txt"],
+    exclude_srcs: ["c.txt"],
+    bazel_module: { bp2build_available: true },
+}`,
+			expectedBazelTargets: []string{`filegroup(
+    name = "fg_foo",
+    srcs = [
+        "//dir:e.txt",
+        "//dir:f.txt",
+        "a.txt",
+        "b.txt",
+    ],
+)`,
+			},
+			fs: map[string]string{
+				"a.txt":          "",
+				"b.txt":          "",
+				"c.txt":          "",
+				"dir/Android.bp": "",
+				"dir/e.txt":      "",
+				"dir/f.txt":      "",
+			},
+		},
+		{
+			description:                        "filegroup in subdir exclude_srcs",
+			moduleTypeUnderTest:                "filegroup",
+			moduleTypeUnderTestFactory:         android.FileGroupFactory,
+			moduleTypeUnderTestBp2BuildMutator: android.FilegroupBp2Build,
+			bp:                                 "",
+			dir:                                "dir",
+			fs: map[string]string{
+				"dir/Android.bp": `filegroup {
+    name: "fg_foo",
+    srcs: ["**/*.txt"],
+    exclude_srcs: ["b.txt"],
+    bazel_module: { bp2build_available: true },
+}
+`,
+				"dir/a.txt":             "",
+				"dir/b.txt":             "",
+				"dir/subdir/Android.bp": "",
+				"dir/subdir/e.txt":      "",
+				"dir/subdir/f.txt":      "",
+			},
+			expectedBazelTargets: []string{`filegroup(
+    name = "fg_foo",
+    srcs = [
+        "//dir/subdir:e.txt",
+        "//dir/subdir:f.txt",
+        "a.txt",
+    ],
+)`,
+			},
+		},
+	}
+
+	dir := "."
+	for _, testCase := range testCases {
+		fs := make(map[string][]byte)
+		toParse := []string{
+			"Android.bp",
+		}
+		for f, content := range testCase.fs {
+			if strings.HasSuffix(f, "Android.bp") {
+				toParse = append(toParse, f)
+			}
+			fs[f] = []byte(content)
+		}
+		config := android.TestConfig(buildDir, nil, testCase.bp, fs)
+		ctx := android.NewTestContext(config)
+		ctx.RegisterModuleType(testCase.moduleTypeUnderTest, testCase.moduleTypeUnderTestFactory)
+		ctx.RegisterBp2BuildMutator(testCase.moduleTypeUnderTest, testCase.moduleTypeUnderTestBp2BuildMutator)
+		ctx.RegisterForBazelConversion()
+
+		_, errs := ctx.ParseFileList(dir, toParse)
+		if Errored(t, testCase.description, errs) {
+			continue
+		}
+		_, errs = ctx.ResolveDependencies(config)
+		if Errored(t, testCase.description, errs) {
+			continue
+		}
+
+		checkDir := dir
+		if testCase.dir != "" {
+			checkDir = testCase.dir
+		}
+		bazelTargets := generateBazelTargetsForDir(NewCodegenContext(config, *ctx.Context, Bp2Build), checkDir)
+		if actualCount, expectedCount := len(bazelTargets), len(testCase.expectedBazelTargets); actualCount != expectedCount {
+			t.Errorf("%s: Expected %d bazel target, got %d\n%s", testCase.description, expectedCount, actualCount, bazelTargets)
+		} else {
+			for i, target := range bazelTargets {
+				if w, g := testCase.expectedBazelTargets[i], target.content; w != g {
+					t.Errorf(
+						"%s: Expected generated Bazel target to be '%s', got '%s'",
+						testCase.description,
+						w,
+						g,
+					)
+				}
+			}
+		}
+	}
+}

bp2build/cc_library_conversion_test.go

@@ -197,6 +197,55 @@ cc_library {
         "//conditions:default": [],
     }),
     srcs = ["ld_android.cpp"],
+)`},
+		},
+		{
+			description:                        "cc_library exclude_srcs - trimmed example of //external/arm-optimized-routines:libarm-optimized-routines-math",
+			moduleTypeUnderTest:                "cc_library",
+			moduleTypeUnderTestFactory:         cc.LibraryFactory,
+			moduleTypeUnderTestBp2BuildMutator: cc.CcLibraryBp2Build,
+			dir:                                "external",
+			filesystem: map[string]string{
+				"external/math/cosf.c":      "",
+				"external/math/erf.c":       "",
+				"external/math/erf_data.c":  "",
+				"external/math/erff.c":      "",
+				"external/math/erff_data.c": "",
+				"external/Android.bp": `
+cc_library {
+    name: "fake-libarm-optimized-routines-math",
+    exclude_srcs: [
+        // Provided by:
+        // bionic/libm/upstream-freebsd/lib/msun/src/s_erf.c
+        // bionic/libm/upstream-freebsd/lib/msun/src/s_erff.c
+        "math/erf.c",
+        "math/erf_data.c",
+        "math/erff.c",
+        "math/erff_data.c",
+    ],
+    srcs: [
+        "math/*.c",
+    ],
+    // arch-specific settings
+    arch: {
+        arm64: {
+            cflags: [
+                "-DHAVE_FAST_FMA=1",
+            ],
+        },
+    },
+    bazel_module: { bp2build_available: true },
+}
+`,
+			},
+			bp: soongCcLibraryPreamble,
+			expectedBazelTargets: []string{`cc_library(
+    name = "fake-libarm-optimized-routines-math",
+    copts = ["-Iexternal"] + select({
+        "//build/bazel/platforms/arch:arm64": ["-DHAVE_FAST_FMA=1"],
+        "//conditions:default": [],
+    }),
+    srcs = ["math/cosf.c"],
 )`},
 		},
 	}