only check special characters on CLI when not in key=value format (#2998)

helper/kv-builder/builder.go

@@ -48,33 +48,36 @@ func (b *Builder) add(raw string) error {
 		return nil
 	}
 
-	// If the arg is exactly "-", then we need to read from stdin
-	// and merge the results into the resulting structure.
-	if raw == "-" {
-		if b.Stdin == nil {
-			return fmt.Errorf("stdin is not supported")
-		}
-		if b.stdin {
-			return fmt.Errorf("stdin already consumed")
-		}
-
-		b.stdin = true
-		return b.addReader(b.Stdin)
-	}
-
-	// If the arg begins with "@" then we need to read a file directly
-	if raw[0] == '@' {
-		f, err := os.Open(raw[1:])
-		if err != nil {
-			return err
-		}
-		defer f.Close()
-
-		return b.addReader(f)
-	}
-
 	// Split into key/value
 	parts := strings.SplitN(raw, "=", 2)
+
+	// If the arg is exactly "-", then we need to read from stdin
+	// and merge the results into the resulting structure.
+	if len(parts) == 1 {
+		if raw == "-" {
+			if b.Stdin == nil {
+				return fmt.Errorf("stdin is not supported")
+			}
+			if b.stdin {
+				return fmt.Errorf("stdin already consumed")
+			}
+
+			b.stdin = true
+			return b.addReader(b.Stdin)
+		}
+
+		// If the arg begins with "@" then we need to read a file directly
+		if raw[0] == '@' {
+			f, err := os.Open(raw[1:])
+			if err != nil {
+				return err
+			}
+			defer f.Close()
+
+			return b.addReader(f)
+		}
+	}
+
 	if len(parts) != 2 {
 		return fmt.Errorf("format must be key=value")
 	}

helper/kv-builder/builder_test.go

@@ -118,3 +118,22 @@ func TestBuilder_sameKeyMultipleTimes(t *testing.T) {
 		t.Fatalf("bad: %#v", actual)
 	}
 }
+
+func TestBuilder_specialCharacteresInKey(t *testing.T) {
+	var b Builder
+	b.Stdin = bytes.NewBufferString("{\"foo\": \"bay\"}")
+	err := b.Add("@foo=bar", "-foo=baz", "-")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	expected := map[string]interface{}{
+		"@foo": "bar",
+		"-foo": "baz",
+		"foo":  "bay",
+	}
+	actual := b.Map()
+	if !reflect.DeepEqual(actual, expected) {
+		t.Fatalf("bad: %#v", actual)
+	}
+}