No longer auto-read from STDIN if there are files given (#1115)

acceptance_tests/basic.sh

@@ -62,11 +62,16 @@ testBasicEvalAllAllFiles() {
   assertEquals "$Y" "$X"
 }
 
+# when given a file, don't read STDIN
+# otherwise strange things start happening
+# in scripts
+# https://github.com/mikefarah/yq/issues/1115
+
 testBasicCatWithFilesNoDash() {
   ./yq -n ".a = 123" > test.yml
   ./yq -n ".a = 124" > test2.yml
   X=$(cat test.yml | ./yq test2.yml)
-  Y=$(./yq e '.' test2.yml test.yml)
+  Y=$(./yq e '.' test2.yml)
   assertEquals "$Y" "$X"
 }
 
@@ -74,7 +79,7 @@ testBasicEvalAllCatWithFilesNoDash() {
   ./yq -n ".a = 123" > test.yml
   ./yq -n ".a = 124" > test2.yml
   X=$(cat test.yml | ./yq ea test2.yml)
-  Y=$(./yq e '.' test2.yml test.yml)
+  Y=$(./yq e '.' test2.yml)
   assertEquals "$Y" "$X"
 }
 
@@ -82,7 +87,7 @@ testBasicCatWithFilesNoDashWithExp() {
   ./yq -n ".a = 123" > test.yml
   ./yq -n ".a = 124" > test2.yml
   X=$(cat test.yml | ./yq '.a' test2.yml)
-  Y=$(./yq e '.a' test2.yml test.yml)
+  Y=$(./yq e '.a' test2.yml)
   assertEquals "$Y" "$X"
 }
 
@@ -90,7 +95,7 @@ testBasicEvalAllCatWithFilesNoDashWithExp() {
   ./yq -n ".a = 123" > test.yml
   ./yq -n ".a = 124" > test2.yml
   X=$(cat test.yml | ./yq ea '.a' test2.yml)
-  Y=$(./yq e '.a' test2.yml test.yml)
+  Y=$(./yq e '.a' test2.yml)
   assertEquals "$Y" "$X"
 }
 

cmd/utils.go

@@ -117,7 +117,11 @@ func maybeFile(str string) bool {
 }
 
 func processStdInArgs(pipingStdin bool, args []string) []string {
-	if !pipingStdin {
+	// if we've been given a file, don't automatically
+	// read from stdin.
+	// this happens if there is more than one argument
+	// or only one argument and its a file
+	if !pipingStdin || len(args) > 1 || (len(args) > 0 && maybeFile(args[0])) {
 		return args
 	}