dep ensure -add should not depend on Go code

CHANGELOG.md

@@ -7,6 +7,7 @@ NEW FEATURES:
 BUG FIXES:
 
 IMPROVEMENTS:
+* dep ensure does not depend on Go code (#1434)
 
 # v0.4.1
 

cmd/dep/ensure.go

@@ -806,9 +806,9 @@ func checkErrors(m map[string]pkgtree.PackageOrErr, ignore *pkgtree.IgnoredRules
 		}
 	}
 
-	// If pkgtree was empty or all dirs lacked any Go code, return an error.
+	// If pkgtree was empty or all dirs lacked any Go code, return a warning.
 	if len(m) == 0 || len(m) == noGoErrors {
-		return true, errors.New("no dirs contained any Go code")
+		return false, errors.New("no dirs contained any Go code")
 	}
 
 	// If all dirs contained build errors, return an error.

cmd/dep/ensure_test.go

@@ -65,6 +65,11 @@ func TestCheckErrors(t *testing.T) {
 		fatal       bool
 		pkgOrErrMap map[string]pkgtree.PackageOrErr
 	}{
+		{
+			name:        "noErrorsAndEmpty",
+			fatal:       false,
+			pkgOrErrMap: map[string]pkgtree.PackageOrErr{},
+		},
 		{
 			name:  "noErrors",
 			fatal: false,
@@ -112,7 +117,7 @@ func TestCheckErrors(t *testing.T) {
 		},
 		{
 			name:  "allGoErrors",
-			fatal: true,
+			fatal: false,
 			pkgOrErrMap: map[string]pkgtree.PackageOrErr{
 				"github.com/me/pkg": {
 					Err: &build.NoGoError{},
@@ -137,10 +142,10 @@ func TestCheckErrors(t *testing.T) {
 		t.Run(tc.name, func(t *testing.T) {
 			fatal, err := checkErrors(tc.pkgOrErrMap, nil)
 			if tc.fatal != fatal {
-				t.Fatalf("expected fatal flag to be %T, got %T", tc.fatal, fatal)
+				t.Fatalf("%s: expected fatal flag to be %t, got %t", tc.name, tc.fatal, fatal)
 			}
 			if err == nil && fatal {
-				t.Fatal("unexpected fatal flag value while err is nil")
+				t.Fatalf("%s: unexpected fatal flag value while err is nil", tc.name)
 			}
 		})
 	}

cmd/dep/testdata/harness_tests/ensure/add/empty-project/final/Gopkg.toml

@@ -0,0 +1,4 @@
+
+[[constraint]]
+  name = "github.com/sdboyer/deptest"
+  version = "1.0.0"

cmd/dep/testdata/harness_tests/ensure/add/empty-project/testcase.json

@@ -0,0 +1,10 @@
+{
+  "commands": [
+    ["init", "-no-examples", "-skip-tools"],
+    ["ensure", "-add", "github.com/sdboyer/deptest"]
+  ],
+  "error-expected": "",
+  "vendor-final": [
+    "github.com/sdboyer/deptest"
+  ]
+}