all: run integration tests against Bash 5.0

Now that 5.0 is released, we should run our tests against that version
instead of 4.4.

Some tests have broken on 5.0, which we'll fix in follow-up commits.

Updates mvdan#346.

interp/interp_test.go

@@ -54,13 +54,13 @@ let i=(2 + 3)
 	}
 }
 
-var hasBash44 bool
+var hasBash50 bool
 
 func TestMain(m *testing.M) {
 	os.Setenv("LANGUAGE", "en_US.UTF8")
 	os.Setenv("LC_ALL", "en_US.UTF8")
 	os.Unsetenv("CDPATH")
-	hasBash44 = checkBash()
+	hasBash50 = checkBash()
 	os.Setenv("INTERP_GLOBAL", "value")
 	os.Setenv("MULTILINE_INTERP_GLOBAL", "\nwith\nnewlines\n\n")
 
@@ -83,7 +83,7 @@ func checkBash() bool {
 	if err != nil {
 		return false
 	}
-	return strings.HasPrefix(string(out), "4.4")
+	return strings.HasPrefix(string(out), "5.0")
 }
 
 // concBuffer wraps a bytes.Buffer in a mutex so that concurrent writes
@@ -2375,8 +2375,8 @@ func TestFileConfirm(t *testing.T) {
 	if testing.Short() {
 		t.Skip("calling bash is slow")
 	}
-	if !hasBash44 {
-		t.Skip("bash 4.4 required to run")
+	if !hasBash50 {
+		t.Skip("bash 5.0 required to run")
 	}
 	if runtime.GOOS == "windows" {
 		// For example, it seems to treat environment variables as

syntax/parser_test.go

@@ -76,15 +76,15 @@ func TestParseMirBSDKorn(t *testing.T) {
 }
 
 var (
-	hasBash44  bool
+	hasBash50  bool
 	hasDash059 bool
 	hasMksh56  bool
 )
 
 func TestMain(m *testing.M) {
 	os.Setenv("LANGUAGE", "en_US.UTF8")
 	os.Setenv("LC_ALL", "en_US.UTF8")
-	hasBash44 = cmdContains("version 4.4", "bash", "--version")
+	hasBash50 = cmdContains("version 5.0", "bash", "--version")
 	// dash provides no way to check its version, so we have to
 	// check if it's new enough as to not have the bug that breaks
 	// our integration tests. Blergh.
@@ -151,8 +151,8 @@ func TestParseBashConfirm(t *testing.T) {
 	if testing.Short() {
 		t.Skip("calling bash is slow.")
 	}
-	if !hasBash44 {
-		t.Skip("bash 4.4 required to run")
+	if !hasBash50 {
+		t.Skip("bash 5.0 required to run")
 	}
 	i := 0
 	for _, c := range append(fileTests, fileTestsNoPrint...) {
@@ -211,8 +211,8 @@ func TestParseErrBashConfirm(t *testing.T) {
 	if testing.Short() {
 		t.Skip("calling bash is slow.")
 	}
-	if !hasBash44 {
-		t.Skip("bash 4.4 required to run")
+	if !hasBash50 {
+		t.Skip("bash 5.0 required to run")
 	}
 	i := 0
 	for _, c := range shellTests {