go/build: call ctxt.match for checking file name constraints

This makes the checking of build tags in file names consistent to that of the build tags in `// +build` line.

Fixed #25461

Change-Id: Iba14d1050f8aba44e7539ab3b8711af1980ccfe4
GitHub-Last-Rev: 11b14e239dd85e11e669919aab45494aee7c59a3
GitHub-Pull-Request: golang/go#25480
Reviewed-on: https://go-review.googlesource.com/113818
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

src/go/build/build.go

@@ -1565,32 +1565,10 @@ func (ctxt *Context) goodOSArchFile(name string, allTags map[string]bool) bool {
 	}
 	n := len(l)
 	if n >= 2 && knownOS[l[n-2]] && knownArch[l[n-1]] {
-		if allTags != nil {
-			allTags[l[n-2]] = true
-			allTags[l[n-1]] = true
-		}
-		if l[n-1] != ctxt.GOARCH {
-			return false
-		}
-		if ctxt.GOOS == "android" && l[n-2] == "linux" {
-			return true
-		}
-		return l[n-2] == ctxt.GOOS
-	}
-	if n >= 1 && knownOS[l[n-1]] {
-		if allTags != nil {
-			allTags[l[n-1]] = true
-		}
-		if ctxt.GOOS == "android" && l[n-1] == "linux" {
-			return true
-		}
-		return l[n-1] == ctxt.GOOS
-	}
-	if n >= 1 && knownArch[l[n-1]] {
-		if allTags != nil {
-			allTags[l[n-1]] = true
+		return ctxt.match(l[n-1], allTags) && ctxt.match(l[n-2], allTags)
 	}
-		return l[n-1] == ctxt.GOARCH
+	if n >= 1 && (knownOS[l[n-1]] || knownArch[l[n-1]]) {
+		return ctxt.match(l[n-1], allTags)
 	}
 	return true
 }

src/go/build/build_test.go

@@ -176,6 +176,18 @@ func TestShouldBuild(t *testing.T) {
 	}
 }
 
+func TestGoodOSArchFile(t *testing.T) {
+	ctx := &Context{BuildTags: []string{"linux"}, GOOS:"darwin"}
+	m := map[string]bool{}
+	want := map[string]bool{"linux": true}
+	if !ctx.goodOSArchFile("hello_linux.go", m) {
+		t.Errorf("goodOSArchFile(hello_linux.go) = false, want true")
+	}
+	if !reflect.DeepEqual(m, want) {
+		t.Errorf("goodOSArchFile(hello_linux.go) tags = %v, want %v", m, want)
+	}
+}
+
 type readNopCloser struct {
 	io.Reader
 }