add happy path tests for two types of imports

test/instrumentation/decode_metric.go

@@ -190,7 +190,7 @@ func (c *metricDecoder) decodeOpts(expr ast.Expr) (metric, error) {
 
 				variableExpr, found := c.variables[strings.Join([]string{s.Name,v.Sel.Name}, ".")]
 				if !found {
-					return m, newDecodeErrorf(expr, errBadVariableAttribute)
+					return m, newDecodeErrorf(expr, errBadImportedVariableAttribute)
 				}
 				bl, ok := variableExpr.(*ast.BasicLit)
 				if !ok {

test/instrumentation/error.go

@@ -23,18 +23,19 @@ import (
 )
 
 const (
-	errNotDirectCall        = "Opts for STABLE metric was not directly passed to new metric function"
+	errNotDirectCall                = "Opts for STABLE metric was not directly passed to new metric function"
-	errPositionalArguments  = "Positional arguments are not supported"
+	errPositionalArguments          = "Positional arguments are not supported"
-	errStabilityLevel       = "StabilityLevel should be passed STABLE, ALPHA or removed"
+	errStabilityLevel               = "StabilityLevel should be passed STABLE, ALPHA or removed"
-	errStableSummary        = "Stable summary metric is not supported"
+	errStableSummary                = "Stable summary metric is not supported"
-	errInvalidNewMetricCall = "Invalid new metric call, please ensure code compiles"
+	errInvalidNewMetricCall         = "Invalid new metric call, please ensure code compiles"
-	errNonStringAttribute   = "Non string attribute is not supported"
+	errNonStringAttribute           = "Non string attribute is not supported"
-	errBadVariableAttribute = "Metric attribute was not correctly set. Please use only global consts in same file"
+	errBadVariableAttribute         = "Metric attribute was not correctly set. Please use only global consts in same file"
-	errFieldNotSupported    = "Field %s is not supported"
+	errBadImportedVariableAttribute = "Metric attribute was not correctly set. Please use only global consts in correclty impoprted same file"
-	errBuckets              = "Buckets should be set to list of floats, result from function call of prometheus.LinearBuckets or prometheus.ExponentialBuckets"
+	errFieldNotSupported            = "Field %s is not supported"
-	errLabels               = "Labels were not set to list of strings"
+	errBuckets                      = "Buckets should be set to list of floats, result from function call of prometheus.LinearBuckets or prometheus.ExponentialBuckets"
-	errImport               = `Importing using "." is not supported`
+	errLabels                       = "Labels were not set to list of strings"
-	errExprNotIdent         = "expr selector does not refer to type ast.Ident, is type %s"
+	errImport                       = `Importing using "." is not supported`
+	errExprNotIdent                 = "expr selector does not refer to type ast.Ident, is type %s"
 )
 
 type decodeError struct {

test/instrumentation/main.go

@@ -46,7 +46,7 @@ var (
 	GOOS string = os.Getenv("GOOS")
 	KUBE_ROOT string = os.Getenv("KUBE_ROOT")
 
-	kubeRootDeSuffixed string = strings.Replace(KUBE_ROOT, kubeURLRoot, "", 1) // k8s/k8s refs need this stripped
+	kubeRootDeSuffixed string = kubeRootDesuffix(KUBE_ROOT)
 )
 
 func main() {
@@ -191,6 +191,9 @@ func globalVariableDeclarations(tree *ast.File) map[string]ast.Expr {
 	return consts
 }
 
+func kubeRootDesuffix(kubeRoot string) string {
+	return strings.Replace(kubeRoot, kubeURLRoot, "", 1) // k8s/k8s refs need this stripped
+}
 
 func localImportPath(importExpr string) (string, error) {
 	// parse directory path

test/instrumentation/main_test.go

@@ -118,9 +118,10 @@ var _ = NewCounter(
 
 func TestStableMetric(t *testing.T) {
 	for _, test := range []struct {
-		testName string
+		testName  string
-		src      string
+		src       string
-		metric   metric
+		metric    metric
+		kubeRoot string
 	}{
 		{
 			testName: "Counter",
@@ -434,9 +435,61 @@ var _ = metrics.NewHistogram(
 			Buckets: metrics.DefBuckets,
 		},
 	)
+`},
+		{
+			testName: "Imported stdlib constant",
+			metric: metric{
+				Name:           "importedCounter",
+				StabilityLevel: "STABLE",
+				Subsystem:      "GET",
+				Type:           counterMetricType,
+			},
+			src: `
+package test
+import "k8s.io/component-base/metrics"
+import "net/http"
+var _ = metrics.NewCounter(
+	&metrics.CounterOpts{
+			Name: "importedCounter",
+			StabilityLevel: metrics.STABLE,
+			Subsystem: http.MethodGet,
+		},
+	)
+`},
+		{
+			testName: "Imported k8s.io constant",
+			metric: metric{
+				Name:           "importedCounter",
+				StabilityLevel: "STABLE",
+				Subsystem:      "kubelet",
+				Type:           counterMetricType,
+			},
+			kubeRoot:  "/home/pchristopher/go/src/k8s.io/kubernetes",
+			src: `
+package test
+import compbasemetrics "k8s.io/component-base/metrics"
+import "k8s.io/kubernetes/pkg/kubelet/metrics"
+var _ = compbasemetrics.NewCounter(
+	&compbasemetrics.CounterOpts{
+			Name: "importedCounter",
+			StabilityLevel: compbasemetrics.STABLE,
+			Subsystem: metrics.KubeletSubsystem,
+	},
+	)
 `},
 	} {
 		t.Run(test.testName, func(t *testing.T) {
+			// these sub-tests cannot be run in parallel with the below
+			if test.kubeRoot != "" {
+				priorKRoot := KUBE_ROOT
+				KUBE_ROOT = test.kubeRoot
+				kubeRootDeSuffixed = kubeRootDesuffix(KUBE_ROOT)
+				defer func(){
+					KUBE_ROOT = priorKRoot
+					kubeRootDeSuffixed = kubeRootDesuffix(KUBE_ROOT)
+				}()
+			}
+
 			metrics, errors := searchFileForStableMetrics(fakeFilename, test.src)
 			if len(errors) != 0 {
 				t.Errorf("Unexpected errors: %s", errors)