Revert "Collect coverage for other languages (bazelbuild#3287)"

This reverts commit d94e692.

go/private/rules/test.bzl

@@ -402,21 +402,11 @@ _go_test_kwargs = {
             default = ["//go/tools/bzltestutil"],
             cfg = go_transition,
         ),
-        # Required for Bazel to collect coverage of instrumented C/C++ binaries
-        # executed by go_test.
-        # This is just a shell script and thus cheap enough to depend on
-        # unconditionally.
-        "_collect_cc_coverage": attr.label(
-            default = "@bazel_tools//tools/test:collect_cc_coverage",
-            cfg = "exec",
-        ),
-        # Required for Bazel to merge coverage reports for Go and other
-        # languages into a single report per test.
-        # Using configuration_field ensures that the tool is only built when
-        # run with bazel coverage, not with bazel test.
+        # Workaround for bazelbuild/bazel#6293. See comment in lcov_merger.sh.
         "_lcov_merger": attr.label(
-            default = configuration_field(fragment = "coverage", name = "output_generator"),
-            cfg = "exec",
+            executable = True,
+            default = "//go/tools/builders:lcov_merger",
+            cfg = "target",
         ),
         "_allowlist_function_transition": attr.label(
             default = "@bazel_tools//tools/allowlists/function_transition_allowlist",

go/tools/builders/BUILD.bazel

@@ -149,6 +149,12 @@ go_reset_target(
     visibility = ["//visibility:public"],
 )
 
+sh_binary(
+    name = "lcov_merger",
+    srcs = ["lcov_merger.sh"],
+    visibility = ["//visibility:public"],
+)
+
 filegroup(
     name = "all_builder_srcs",
     testonly = True,

go/tools/builders/lcov_merger.sh

@@ -0,0 +1,21 @@
+#!/usr/bin/env bash
+
+# Copyright 2018 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.
+
+# This is a workaround for bazelbuild/bazel#6293. Since Bazel 0.18.0, Bazel
+# expects tests to have an "$lcov_merger' or "_lcov_merger" attribute that
+# points to an executable. If this is missing, the test driver fails.
+
+exit 0

go/tools/bzltestutil/lcov.go

@@ -33,7 +33,13 @@ import (
 // Bazel.
 // The conversion emits line and branch coverage, but not function coverage.
 func ConvertCoverToLcov() error {
+	// The value of test.coverprofile has been set to
+	// ${COVERAGE_OUTPUT_PATH}.cover by the generated TestMain. We have to strip
+	// the ".cover" suffix here so that the generated expectedLcov report is at the
+	// location where Bazel's expectedLcov merge picks it up.
 	inPath := flag.Lookup("test.coverprofile").Value.String()
+	outPath := strings.TrimSuffix(inPath, ".cover")
+
 	in, err := os.Open(inPath)
 	if err != nil {
 		// This can happen if there are no tests and should not be an error.
@@ -42,8 +48,7 @@ func ConvertCoverToLcov() error {
 	}
 	defer in.Close()
 
-	// All *.dat files in $COVERAGE_DIR will be merged by Bazel's lcov_merger tool.
-	out, err := os.CreateTemp(os.Getenv("COVERAGE_DIR"), "go_coverage.*.dat")
+	out, err := os.Create(outPath)
 	if err != nil {
 		return err
 	}
@@ -57,8 +62,8 @@ var _coverLinePattern = regexp.MustCompile(`^(?P<path>.+):(?P<startLine>\d+)\.(?
 const (
 	_pathIdx      = 1
 	_startLineIdx = 2
-	_endLineIdx   = 4
-	_countIdx     = 7
+	_endLineIdx = 4
+	_countIdx   = 7
 )
 
 func convertCoverToLcov(coverReader io.Reader, lcovWriter io.Writer) error {

tests/core/coverage/lcov_coverage_test.go

@@ -47,18 +47,6 @@ go_test(
     srcs = ["lib_test.go"],
     deps = [":lib"],
 )
-
-java_binary(
-    name = "Tool",
-    srcs = ["Tool.java"],
-)
-
-go_test(
-    name = "lib_with_tool_test",
-    srcs = ["lib_with_tool_test.go"],
-    data = [":Tool"],
-    deps = [":lib"],
-)
 -- src/lib.go --
 package lib
 
@@ -102,40 +90,6 @@ func TestLib(t *testing.T) {
 		t.Error("Expected a newline in the output")
 	}
 }
--- src/Tool.java --
-public class Tool {
-  public static void main(String[] args) {
-    if (args.length != 0) {
-      System.err.println("Expected no arguments");
-      System.exit(1);
-    }
-    System.err.println("Hello, world!");
-  }
-}
--- src/lib_with_tool_test.go --
-package lib_test
-
-import (
-	"os/exec"
-	"strings"
-	"testing"
-
-	"example.com/lib"
-)
-
-func TestLib(t *testing.T) {
-	if !strings.Contains(lib.HelloFromLib(false), "\n") {
-		t.Error("Expected a newline in the output")
-	}
-}
-
-func TestTool(t *testing.T) {
-	err := exec.Command("Tool").Run()
-	if err != nil {
-		t.Error(err)
-	}
-}
-
 `,
 	})
 }
@@ -166,7 +120,7 @@ func testLcovCoverage(t *testing.T, extraArgs ...string) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	for _, expectedIndividualCoverage := range expectedGoCoverage {
+	for _, expectedIndividualCoverage := range expectedIndividualCoverages {
 		if !strings.Contains(string(individualCoverageData), expectedIndividualCoverage) {
 			t.Errorf(
 				"%s: does not contain:\n\n%s\nactual content:\n\n%s",
@@ -192,54 +146,8 @@ func testLcovCoverage(t *testing.T, extraArgs ...string) {
 	}
 }
 
-func TestLcovCoverageWithTool(t *testing.T) {
-	args := append([]string{
-		"coverage",
-		"--combined_report=lcov",
-		"//src:lib_with_tool_test",
-	})
-
-	if err := bazel_testing.RunBazel(args...); err != nil {
-		t.Fatal(err)
-	}
-
-	individualCoveragePath := filepath.FromSlash("bazel-testlogs/src/lib_with_tool_test/coverage.dat")
-	individualCoverageData, err := ioutil.ReadFile(individualCoveragePath)
-	if err != nil {
-		t.Fatal(err)
-	}
-	expectedCoverage := append(expectedGoCoverage, expectedToolCoverage)
-	for _, expected := range expectedCoverage {
-		if !strings.Contains(string(individualCoverageData), expected) {
-			t.Errorf(
-				"%s: does not contain:\n\n%s\nactual content:\n\n%s",
-				individualCoveragePath,
-				expected,
-				string(individualCoverageData),
-			)
-		}
-	}
-
-	combinedCoveragePath := filepath.FromSlash("bazel-out/_coverage/_coverage_report.dat")
-	combinedCoverageData, err := ioutil.ReadFile(combinedCoveragePath)
-	if err != nil {
-		t.Fatal(err)
-	}
-	for _, include := range []string{
-		"SF:src/lib.go\n",
-		"SF:src/other_lib.go\n",
-		"SF:src/Tool.java\n",
-	} {
-		if !strings.Contains(string(combinedCoverageData), include) {
-			t.Errorf("%s: does not contain %q\n", combinedCoverageData, include)
-		}
-	}
-}
-
-var expectedGoCoverage = []string{
+var expectedIndividualCoverages = []string{
 	`SF:src/other_lib.go
-FNF:0
-FNH:0
 DA:3,1
 DA:4,1
 DA:5,0
@@ -250,8 +158,6 @@ LF:5
 end_of_record
 `,
 	`SF:src/lib.go
-FNF:0
-FNH:0
 DA:9,1
 DA:10,1
 DA:11,1
@@ -265,25 +171,3 @@ LH:8
 LF:9
 end_of_record
 `}
-
-const expectedToolCoverage = `SF:src/Tool.java
-FN:1,Tool::<init> ()V
-FN:3,Tool::main ([Ljava/lang/String;)V
-FNDA:0,Tool::<init> ()V
-FNDA:1,Tool::main ([Ljava/lang/String;)V
-FNF:2
-FNH:1
-BRDA:3,0,0,1
-BRDA:3,0,1,0
-BRF:2
-BRH:1
-DA:1,0
-DA:3,1
-DA:4,0
-DA:5,0
-DA:7,1
-DA:8,1
-LH:3
-LF:6
-end_of_record
-`

tests/core/coverage/lcov_test_main_coverage_test.go

@@ -108,8 +108,6 @@ func TestLcovCoverageWithTestMain(t *testing.T) {
 }
 
 const expectedIndividualCoverage = `SF:src/lib.go
-FNF:0
-FNH:0
 DA:3,1
 DA:4,1
 DA:5,0