cmd/gb: expand boolean flags when passed to test subprocess (#608)

Fixes #605

Goconvey, and probably others, do not parse flags, they just string
match against `os.Args`. Because of this the semantically identical,
`-test.v` and `-test.v=true` are not identical. Fix this by expanding
boolean arguments that are passed to the test subprocess.

cmd/gb/gb_test.go

@@ -1661,3 +1661,34 @@ func main() {
 	gb.run("build")
 	gb.mustBeEmpty(tmpdir)
 }
+
+// goconvey (and probably others) do not parse flags passed to the
+// test binary, they just expect them to be present in their raw form
+// in os.Args. As such -test.v and -test.v=true are not the same.
+// Assert that gb is passing the latter form.
+func TestIssue605(t *testing.T) {
+	gb := T{T: t}
+	defer gb.cleanup()
+
+	gb.tempDir("src/issue605")
+	gb.tempFile("src/issue605/issue_test.go", `package issue605
+
+import (
+        "os"
+        "testing"
+)
+
+func TestFlags(t *testing.T) {
+        for _, f := range os.Args {
+                if f == "-test.v=true" {
+                        return
+                }
+        }
+        t.Fatalf("could not find test flag: %q", os.Args)
+}`)
+	gb.cd(gb.tempdir)
+	tmpdir := gb.tempDir("tmp")
+	gb.run("test", "-v") // should translate into -test.v=true
+	gb.mustBeEmpty(tmpdir)
+
+}

cmd/gb/testflag.go

@@ -75,6 +75,13 @@ func TestFlags(testArgs []string) []string {
 				}
 				if val.passToTest || val.passToAll {
 					fArg = "-test." + nArg
+					if val.boolVar {
+						// boolean variables can be either -bool, or -bool=true
+						// some code, see issue 605, expects the latter form, so
+						// when present, expand boolean args to their canonical
+						// form.
+						nVal = "true"
+					}
 					if nVal != "" {
 						fArg = fArg + "=" + nVal
 					}

cmd/gb/testflag_test.go

@@ -146,10 +146,10 @@ func TestTestFlags(t *testing.T) {
 	}{
 		{
 			eargs: []string{"-q", "-debug"},
-			targs: []string{"-test.v", "-debug"},
+			targs: []string{"-test.v=true", "-debug"},
 		}, {
 			eargs: []string{"-v", "-debug"},
-			targs: []string{"-test.v", "-debug"},
+			targs: []string{"-test.v=true", "-debug"},
 		}, {
 			eargs: []string{"-bench"},
 			targs: []string{"-test.bench"},
@@ -161,7 +161,7 @@ func TestTestFlags(t *testing.T) {
 			targs: []string{"-test.bench='Test*'"},
 		}, {
 			eargs: []string{"-benchmem"},
-			targs: []string{"-test.benchmem"},
+			targs: []string{"-test.benchmem=true"},
 		}, {
 			eargs: []string{"-benchtime"},
 			targs: []string{"-test.benchtime"},
@@ -188,7 +188,7 @@ func TestTestFlags(t *testing.T) {
 			targs: []string{"-test.memprofile"},
 		}, {
 			eargs: []string{"-short"},
-			targs: []string{"-test.short"},
+			targs: []string{"-test.short=true"},
 		}, {
 			eargs: []string{"-memprofilerate", "1"},
 			targs: []string{"-test.memprofilerate", "1"},