Introduce new rlocation helper function for AK

PiperOrigin-RevId: 516530149
Change-Id: Iad2eaac6ffeb1b86c955cd70ec345c6c22253228

4 files changed, 114 insertions, 3 deletions

diff --git a/prereqs.bzl b/prereqs.bzl
index d106a88..c2dc015 100644
--- a/prereqs.bzl
+++ b/prereqs.bzl
@@ -59,10 +59,10 @@ def rules_android_prereqs():
     maybe(
         http_archive,
         name = "io_bazel_rules_go",
-        sha256 = "16e9fca53ed6bd4ff4ad76facc9b7b651a89db1689a2877d6fd7b82aa824e366",
+        sha256 = "dd926a88a564a9246713a9c00b35315f54cbd46b31a26d5d8fb264c07045f05d",
         urls = [
-            "https://mirror.bazel.build/github.com/bazelbuild/rules_go/releases/download/v0.34.0/rules_go-v0.34.0.zip",
-            "https://github.com/bazelbuild/rules_go/releases/download/v0.34.0/rules_go-v0.34.0.zip",
+            "https://mirror.bazel.build/github.com/bazelbuild/rules_go/releases/download/v0.38.1/rules_go-v0.38.1.zip",
+            "https://github.com/bazelbuild/rules_go/releases/download/v0.38.1/rules_go-v0.38.1.zip",
         ],
     )
 
diff --git a/src/common/golang/BUILD b/src/common/golang/BUILD
index 23d2761..4c1bf0f 100644
--- a/src/common/golang/BUILD
+++ b/src/common/golang/BUILD
@@ -94,3 +94,23 @@ go_library(
     srcs = ["flagfile.go"],
     importpath = "src/common/golang/flagfile",
 )
+
+genrule(
+    name = "a_txt",
+    outs = ["a.txt"],
+    cmd = "echo hello world > $@",
+)
+
+go_library(
+    name = "runfilelocation",
+    srcs = ["runfilelocation.go"],
+    importpath = "src/common/golang/runfilelocation",
+    deps = ["@io_bazel_rules_go//go/runfiles"],
+)
+
+go_test(
+    name = "runfilelocation_test",
+    srcs = ["runfilelocation_test.go"],
+    data = [":a_txt"],
+    embed = [":runfilelocation"],
+)
diff --git a/src/common/golang/runfilelocation.go b/src/common/golang/runfilelocation.go
new file mode 100644
index 0000000..b2eb5d6
--- /dev/null
+++ b/src/common/golang/runfilelocation.go
@@ -0,0 +1,40 @@
+// Copyright 2023 The Bazel Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package runfilelocation provides utility functions to deal with runfiles
+
+package runfilelocation
+
+import (
+	"os"
+	"path"
+
+	"github.com/bazelbuild/rules_go/go/runfiles"
+)
+
+// Find determines the absolute path to a given runfile
+func Find(runfilePath string) (string, error) {
+	runfileLocation, err := runfiles.Rlocation(path.Join(os.Getenv("TEST_WORKSPACE"), runfilePath))
+
+	if err != nil {
+		return "", err
+	}
+
+	// Check if file exists
+	if _, err := os.Stat(runfileLocation); err != nil {
+		return "", err
+	}
+
+	return runfileLocation, err
+}
diff --git a/src/common/golang/runfilelocation_test.go b/src/common/golang/runfilelocation_test.go
new file mode 100644
index 0000000..b2f3fb4
--- /dev/null
+++ b/src/common/golang/runfilelocation_test.go
@@ -0,0 +1,51 @@
+// Copyright 2023 The Bazel Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package runfilelocation
+
+import (
+	"io/ioutil"
+	"testing"
+)
+
+func TestValidRunfileLocation(t *testing.T) {
+	// Check that Find() returns a valid path to a runfile
+	runfilePath := "src/common/golang/a.txt"
+
+	absRunFilePath, err := Find(runfilePath)
+	if err != nil {
+		t.Errorf("Runfile path through Runfilelocation() failed: %v", err)
+	}
+
+	// Check that the path actually exists
+	contents, err := ioutil.ReadFile(absRunFilePath)
+	text := string(contents)
+	if err != nil {
+		t.Errorf("Could not read file: %v", err)
+	}
+
+	if text != "hello world\n" {
+		t.Errorf("Expected 'hello world' in file, got %v instead.", text)
+	}
+}
+
+func TestInvalidRunfileLocation(t *testing.T) {
+	invalidRunfilePath := "src/common/golang/b.txt"
+
+	runfileLocationShouldNotExist, err := Find(invalidRunfilePath)
+	if err == nil {
+		// If no error, that means the library is not properly detecting invalid runfile paths
+		t.Errorf("Expected error: %v should not be a valid path. Returned %v", invalidRunfilePath, runfileLocationShouldNotExist)
+	}
+}