Improve error message when calling a builtin function with wrong type

Error message is simpler and doesn't show the type of all arguments.

RELNOTES: None.
PiperOrigin-RevId: 161187134

2 files changed, 7 insertions, 9 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/syntax/BuiltinFunction.java b/src/main/java/com/google/devtools/build/lib/syntax/BuiltinFunction.java
index b3c742f148..5852386729 100644
--- a/src/main/java/com/google/devtools/build/lib/syntax/BuiltinFunction.java
+++ b/src/main/java/com/google/devtools/build/lib/syntax/BuiltinFunction.java
@@ -186,17 +186,15 @@ public class BuiltinFunction extends BaseFunction {
         if (args[i] != null && !types[i].isAssignableFrom(args[i].getClass())) {
           String paramName =
               i < len ? signature.getSignature().getNames().get(i) : extraArgs[i - len].name();
-          int extraArgsCount = (extraArgs == null) ? 0 : extraArgs.length;
           throw new EvalException(
               loc,
               String.format(
-                  "method %s is not applicable for arguments %s: "
-                      + "'%s' is '%s', but should be '%s'",
-                  getShortSignature(),
-                  printTypeString(args, args.length - extraArgsCount),
+                  "argument '%s' has type '%s', but should be '%s'\nin call to builtin %s %s",
                   paramName,
                   EvalUtils.getDataTypeName(args[i]),
-                  EvalUtils.getDataTypeNameFromClass(types[i])));
+                  EvalUtils.getDataTypeNameFromClass(types[i]),
+                  hasSelfArgument() ? "method" : "function",
+                  getShortSignature()));
         }
       }
       throw badCallException(loc, e, args);
diff --git a/src/main/java/com/google/devtools/build/lib/syntax/FunctionSignature.java b/src/main/java/com/google/devtools/build/lib/syntax/FunctionSignature.java
index 3b12fd5425..5dc2a6a5c6 100644
--- a/src/main/java/com/google/devtools/build/lib/syntax/FunctionSignature.java
+++ b/src/main/java/com/google/devtools/build/lib/syntax/FunctionSignature.java
@@ -391,7 +391,7 @@ public abstract class FunctionSignature implements Serializable {
     public StringBuilder toStringBuilder(
         final StringBuilder sb,
         final boolean showDefaults,
-        final boolean skipMissingTypeNames,
+        final boolean showTypes,
         final boolean skipFirstMandatory) {
       FunctionSignature signature = getSignature();
       Shape shape = signature.getShape();
@@ -431,9 +431,9 @@ public abstract class FunctionSignature implements Serializable {
           // a) there is no type defined (such as in user-defined functions) or
           // b) the type is java.lang.Object.
           boolean typeDefined = types != null && types.get(i) != null;
-          if (typeDefined || !skipMissingTypeNames) {
+          if (typeDefined && showTypes) {
             printer.append(": ");
-            printer.append(typeDefined ? types.get(i).toString() : "object");
+            printer.append(types.get(i).toString());
           }
         }
         public void mandatory(int i) {