Allow non capturing groups (#9)

Fix the flags parsing to accept regexes with non capturing groups

Signed-off-by: Tom <[email protected]>

analyzer_test.go

@@ -13,6 +13,32 @@ import (
 	"golang.org/x/tools/go/analysis/passes/inspect"
 )
 
+func makeAnalyzer() *analysis.Analyzer {
+	cnf := Config{
+		RequiredAlias: make(map[string]string),
+	}
+	return &analysis.Analyzer{
+		Flags: flags(&cnf),
+		Run: func(pass *analysis.Pass) (interface{}, error) {
+			return runWithConfig(&cnf, pass)
+		},
+		Requires: []*analysis.Analyzer{inspect.Analyzer},
+	}
+}
+
+func TestIncorrectFlags(t *testing.T) {
+	assertWrongAliasErr := func(msg string, err error) {
+		if err == nil || err.Error() != errWrongAlias.Error() {
+			t.Errorf("Wrong error for invalid usage[%q]: %v", msg, err)
+		}
+	}
+	a := makeAnalyzer()
+	flg := a.Flags.Lookup("alias")
+	assertWrongAliasErr("empty flag", flg.Value.Set(""))
+	assertWrongAliasErr("white space only", flg.Value.Set("   "))
+	assertWrongAliasErr("no colons", flg.Value.Set("no colons"))
+}
+
 func TestAnalyzer(t *testing.T) {
 	testdata := analysistest.TestData()
 
@@ -70,6 +96,13 @@ func TestAnalyzer(t *testing.T) {
 			pkg:                  "f",
 			disallowExtraAliases: true,
 		},
+		{
+			desc: "regexp with non capturing groups",
+			pkg:  "g",
+			aliases: stringMap{
+				"knative.dev/serving/pkg/(?:apis/)?(\\w+)(?:/v[\\w\\d]+)?": "k$1",
+			},
+		},
 	}
 
 	for _, test := range testCases {
@@ -91,19 +124,7 @@ func TestAnalyzer(t *testing.T) {
 					t.Fatal(err, string(output))
 				}
 			}
-
-			cnf := Config{
-				RequiredAlias: make(map[string]string),
-			}
-			flgs := flags(&cnf)
-			a := &analysis.Analyzer{
-				Flags: flgs,
-				Run: func(pass *analysis.Pass) (interface{}, error) {
-					return runWithConfig(&cnf, pass)
-				},
-				Requires: []*analysis.Analyzer{inspect.Analyzer},
-			}
-
+			a := makeAnalyzer()
 			flg := a.Flags.Lookup("alias")
 			for k, v := range test.aliases {
 				err := flg.Value.Set(fmt.Sprintf("%s:%s", k, v))
@@ -117,8 +138,8 @@ func TestAnalyzer(t *testing.T) {
 				t.Fatal(err)
 			}
 
-			noExtraAlisesFlg := a.Flags.Lookup("no-extra-aliases")
-			if err := noExtraAlisesFlg.Value.Set(strconv.FormatBool(test.disallowExtraAliases)); err != nil {
+			noExtraAliasesFlg := a.Flags.Lookup("no-extra-aliases")
+			if err := noExtraAliasesFlg.Value.Set(strconv.FormatBool(test.disallowExtraAliases)); err != nil {
 				t.Fatal(err)
 			}
 

flags.go

@@ -7,6 +7,8 @@ import (
 	"strings"
 )
 
+var errWrongAlias = errors.New("import flag must be of form path:alias")
+
 func flags(config *Config) flag.FlagSet {
 	fs := flag.FlagSet{}
 	fs.Var(stringMap(config.RequiredAlias), "alias", "required import alias in form path:alias")
@@ -18,12 +20,11 @@ func flags(config *Config) flag.FlagSet {
 type stringMap map[string]string
 
 func (v stringMap) Set(val string) error {
-	spl := strings.SplitN(val, ":", 2)
-	if len(spl) != 2 {
-		return errors.New("import flag must be of form path:alias")
+	lastColon := strings.LastIndex(val, ":")
+	if lastColon <= 1 {
+		return errWrongAlias
 	}
-
-	v[spl[0]] = spl[1]
+	v[val[:lastColon]] = val[lastColon+1:]
 	return nil
 }
 

testdata/src/d/d.go

@@ -1,4 +1,4 @@
-package c
+package d
 
 import (
 	v1alpha1 "knative.dev/serving/pkg/apis/autoscaling/v1alpha1" // want `import "knative.dev/serving/pkg/apis/autoscaling/v1alpha1" imported as "v1alpha1" but must be "autoscalingv1alpha1" according to config`

testdata/src/d/d.go.golden

@@ -1,4 +1,4 @@
-package c
+package d
 
 import (
 	autoscalingv1alpha1 "knative.dev/serving/pkg/apis/autoscaling/v1alpha1" // want `import "knative.dev/serving/pkg/apis/autoscaling/v1alpha1" imported as "v1alpha1" but must be "autoscalingv1alpha1" according to config`

testdata/src/d/go.mod

@@ -1,4 +1,4 @@
-module github.com/julz/importas/testdata/src/c
+module github.com/julz/importas/testdata/src/d
 
 go 1.15
 

testdata/src/g/g.go

@@ -0,0 +1,10 @@
+package g
+
+import (
+	v1 "knative.dev/serving/pkg/apis/serving/v1" // want `import "knative.dev/serving/pkg/apis/serving/v1" imported as "v1" but must be "kserving" according to config`
+	knative1 "knative.dev/serving/pkg/queue"     // want `import "knative.dev/serving/pkg/queue" imported as "knative1" but must be "kqueue" according to config`
+)
+
+func foo() {
+	v1.Resource(knative1.Name)
+}

testdata/src/g/g.go.golden

@@ -0,0 +1,10 @@
+package g
+
+import (
+	kserving "knative.dev/serving/pkg/apis/serving/v1" // want `import "knative.dev/serving/pkg/apis/serving/v1" imported as "v1" but must be "kserving" according to config`
+	kqueue "knative.dev/serving/pkg/queue"             // want `import "knative.dev/serving/pkg/queue" imported as "knative1" but must be "kqueue" according to config`
+)
+
+func foo() {
+	kserving.Resource(kqueue.Name)
+}

testdata/src/g/go.mod

@@ -0,0 +1,5 @@
+module github.com/julz/importas/testdata/src/g
+
+go 1.15
+
+require knative.dev/serving v0.21.0