Make 'make cover' faster

2 files changed, 111 insertions, 6 deletions

diff --git a/Makefile b/Makefile
index aaa9165e5..490e230fd 100644
--- a/Makefile
+++ b/Makefile
@@ -172,12 +172,7 @@ cover: prepare-tests $(GOCOVMERGE)
 	@echo "NOTE: make cover does not exit 1 on failure, don't use it to check for tests success!"
 	mkdir -p "$(COVERAGE_DIR)"
 	rm -f $(COVERAGE_DIR)/*.out "$(COVERAGE_DIR)/all.merged" "$(COVERAGE_DIR)/all.html"
-	echo $(LOCAL_PACKAGES) > $(TARGET_DIR)/local_packages
-	for MOD in `cat $(TARGET_DIR)/local_packages`; do \
-		go test -coverpkg=`cat $(TARGET_DIR)/local_packages |tr " " "," ` \
-			-coverprofile=$(COVERAGE_DIR)/unit-`echo $$MOD|tr "/" "_"`.out \
-			$$MOD 2>&1 | grep -v "no packages being tested depend on"; \
-	done
+	go run _support/test-cover-parallel.go $(COVERAGE_DIR) $(LOCAL_PACKAGES)
 	$(GOCOVMERGE) $(COVERAGE_DIR)/*.out > "$(COVERAGE_DIR)/all.merged"
 	go tool cover -html  "$(COVERAGE_DIR)/all.merged" -o "$(COVERAGE_DIR)/all.html"
 	@echo ""
diff --git a/_support/test-cover-parallel.go b/_support/test-cover-parallel.go
new file mode 100644
index 000000000..2719f6d3c
--- /dev/null
+++ b/_support/test-cover-parallel.go
@@ -0,0 +1,110 @@
+package main
+
+import (
+	"fmt"
+	"log"
+	"os"
+	"os/exec"
+	"strings"
+	"sync"
+	"time"
+)
+
+const (
+	progName = "test-cover-parallel.go"
+)
+
+func main() {
+	if len(os.Args) <= 2 {
+		log.Fatalf("usage %s OUT_DIR PKG [PKG...]", progName)
+	}
+
+	outDir := os.Args[1]
+	packages := os.Args[2:]
+
+	if err := buildDependentPackages(packages); err != nil {
+		log.Fatal(err)
+	}
+
+	numWorkers := 2
+	cmdChan := make(chan *exec.Cmd)
+	wg := &sync.WaitGroup{}
+	for i := 0; i < numWorkers; i++ {
+		wg.Add(1)
+		go func() {
+			for cmd := range cmdChan {
+				runCover(cmd)
+			}
+			wg.Done()
+		}()
+	}
+
+	packageMap := make(map[string]bool, len(packages))
+	for _, pkg := range packages {
+		packageMap[pkg] = true
+	}
+
+	for _, pkg := range packages {
+		deps, err := depsForPackage(pkg, packageMap)
+		if err != nil {
+			log.Fatal(err)
+		}
+
+		args := []string{
+			"go",
+			"test",
+			fmt.Sprintf("-coverpkg=%s", strings.Join(deps, ",")),
+			fmt.Sprintf("-coverprofile=%s/unit-%s.out", outDir, strings.Replace(pkg, "/", "_", -1)),
+			pkg,
+		}
+
+		cmdChan <- exec.Command(args[0], args[1:]...)
+	}
+	close(cmdChan)
+
+	wg.Wait()
+}
+
+func depsForPackage(pkg string, packageMap map[string]bool) ([]string, error) {
+	depsOut, err := exec.Command("go", "list", "-f", `{{ join .Deps "\n" }}`, pkg).Output()
+	if err != nil {
+		return nil, err
+	}
+
+	deps := []string{pkg}
+	for _, d := range strings.Split(string(depsOut), "\n") {
+		if packageMap[d] {
+			deps = append(deps, d)
+		}
+	}
+
+	return deps, nil
+}
+
+func buildDependentPackages(packages []string) error {
+	buildDeps := exec.Command("go", append([]string{"test", "-i"}, packages...)...)
+	buildDeps.Stdout = os.Stdout
+	buildDeps.Stderr = os.Stderr
+	start := time.Now()
+	if err := buildDeps.Run(); err != nil {
+		log.Printf("command failed: %s", strings.Join(buildDeps.Args, " "))
+		return err
+	}
+	log.Printf("go test -i\t%.3fs", time.Since(start).Seconds())
+	return nil
+}
+
+func runCover(cmd *exec.Cmd) {
+	start := time.Now()
+	err := cmd.Run()
+	duration := time.Since(start)
+
+	status := fmt.Sprintf("%s\t%.3fs", cmd.Args[len(cmd.Args)-1], duration.Seconds())
+
+	if err != nil {
+		fmt.Printf("FAIL\t%s\n", status)
+		fmt.Printf("command was: %s\n", strings.Join(cmd.Args, " "))
+	} else {
+		fmt.Printf("ok  \t%s\n", status)
+	}
+}