Simplify arity errors, rewording spread errors (#43855)

* Scribbles + tests

The second test actually requires node types

* Basically working

The two simple fixes, in arity error reporting, are in, and the
simplification of arity error reporting is half-done. I haven't started
on any improvements to call assignability.

* trim out too-real test case

* Finish cleanup

And reword error a little.

* Simplify and reword spread errors

* handle spreads first

* update baselines

* Address PR comments

Author: sandersn

src/compiler/checker.ts

@@ -28613,88 +28613,67 @@ namespace ts {
         }
 
         function getArgumentArityError(node: CallLikeExpression, signatures: readonly Signature[], args: readonly Expression[]) {
-            let min = Number.POSITIVE_INFINITY;
-            let max = Number.NEGATIVE_INFINITY;
-            let belowArgCount = Number.NEGATIVE_INFINITY;
-            let aboveArgCount = Number.POSITIVE_INFINITY;
+            const spreadIndex = getSpreadArgumentIndex(args);
+            if (spreadIndex > -1) {
+                return createDiagnosticForNode(args[spreadIndex], Diagnostics.A_spread_argument_must_either_have_a_tuple_type_or_be_passed_to_a_rest_parameter);
+            }
+            let min = Number.POSITIVE_INFINITY; // smallest parameter count
+            let max = Number.NEGATIVE_INFINITY; // largest parameter count
+            let maxBelow = Number.NEGATIVE_INFINITY; // largest parameter count that is smaller than the number of arguments
+            let minAbove = Number.POSITIVE_INFINITY; // smallest parameter count that is larger than the number of arguments
 
-            let argCount = args.length;
             let closestSignature: Signature | undefined;
             for (const sig of signatures) {
-                const minCount = getMinArgumentCount(sig);
-                const maxCount = getParameterCount(sig);
-                if (minCount < argCount && minCount > belowArgCount) belowArgCount = minCount;
-                if (argCount < maxCount && maxCount < aboveArgCount) aboveArgCount = maxCount;
-                if (minCount < min) {
-                    min = minCount;
+                const minParameter = getMinArgumentCount(sig);
+                const maxParameter = getParameterCount(sig);
+                // smallest/largest parameter counts
+                if (minParameter < min) {
+                    min = minParameter;
                     closestSignature = sig;
                 }
-                max = Math.max(max, maxCount);
-            }
-
-            if (min < argCount && argCount < max) {
-                return getDiagnosticForCallNode(node, Diagnostics.No_overload_expects_0_arguments_but_overloads_do_exist_that_expect_either_1_or_2_arguments, argCount, belowArgCount, aboveArgCount);
+                max = Math.max(max, maxParameter);
+                // shortest parameter count *longer than the call*/longest parameter count *shorter than the call*
+                if (minParameter < args.length && minParameter > maxBelow) maxBelow = minParameter;
+                if (args.length < maxParameter && maxParameter < minAbove) minAbove = maxParameter;
             }
-
             const hasRestParameter = some(signatures, hasEffectiveRestParameter);
-            const paramRange = hasRestParameter ? min :
-                min < max ? min + "-" + max :
-                min;
-            const hasSpreadArgument = getSpreadArgumentIndex(args) > -1;
-            if (argCount <= max && hasSpreadArgument) {
-                argCount--;
-            }
-
-            let spanArray: NodeArray<Node>;
-            let related: DiagnosticWithLocation | undefined;
-
-            const error = hasRestParameter || hasSpreadArgument ?
-                hasRestParameter && hasSpreadArgument ?
-                    Diagnostics.Expected_at_least_0_arguments_but_got_1_or_more :
-                    hasRestParameter ?
-                        Diagnostics.Expected_at_least_0_arguments_but_got_1 :
-                        Diagnostics.Expected_0_arguments_but_got_1_or_more :
-                    paramRange === 1 && argCount === 0 && isPromiseResolveArityError(node) ?
-                        Diagnostics.Expected_0_arguments_but_got_1_Did_you_forget_to_include_void_in_your_type_argument_to_Promise :
-                        Diagnostics.Expected_0_arguments_but_got_1;
-
-            if (closestSignature && getMinArgumentCount(closestSignature) > argCount && closestSignature.declaration) {
-                const paramDecl = closestSignature.declaration.parameters[closestSignature.thisParameter ? argCount + 1 : argCount];
-                if (paramDecl) {
-                    related = createDiagnosticForNode(
-                        paramDecl,
-                        isBindingPattern(paramDecl.name) ? Diagnostics.An_argument_matching_this_binding_pattern_was_not_provided :
-                            isRestParameter(paramDecl) ? Diagnostics.Arguments_for_the_rest_parameter_0_were_not_provided : Diagnostics.An_argument_for_0_was_not_provided,
-                        !paramDecl.name ? argCount : !isBindingPattern(paramDecl.name) ? idText(getFirstIdentifier(paramDecl.name)) : undefined
+            const parameterRange = hasRestParameter ? min
+                : min < max ? min + "-" + max
+                : min;
+            const error = hasRestParameter ? Diagnostics.Expected_at_least_0_arguments_but_got_1
+                : parameterRange === 1 && args.length === 0 && isPromiseResolveArityError(node) ? Diagnostics.Expected_0_arguments_but_got_1_Did_you_forget_to_include_void_in_your_type_argument_to_Promise
+                : Diagnostics.Expected_0_arguments_but_got_1;
+            if (min < args.length && args.length < max) {
+                // between min and max, but with no matching overload
+                return getDiagnosticForCallNode(node, Diagnostics.No_overload_expects_0_arguments_but_overloads_do_exist_that_expect_either_1_or_2_arguments, args.length, maxBelow, minAbove);
+            }
+            else if (args.length < min) {
+                // too short: put the error span on the call expression, not any of the args
+                const diagnostic = getDiagnosticForCallNode(node, error, parameterRange, args.length);
+                const parameter = closestSignature?.declaration?.parameters[closestSignature.thisParameter ? args.length + 1 : args.length];
+                if (parameter) {
+                    const parameterError = createDiagnosticForNode(
+                        parameter,
+                        isBindingPattern(parameter.name) ? Diagnostics.An_argument_matching_this_binding_pattern_was_not_provided
+                            : isRestParameter(parameter) ? Diagnostics.Arguments_for_the_rest_parameter_0_were_not_provided
+                            : Diagnostics.An_argument_for_0_was_not_provided,
+                        !parameter.name ? args.length : !isBindingPattern(parameter.name) ? idText(getFirstIdentifier(parameter.name)) : undefined
                     );
+                    return addRelatedInfo(diagnostic, parameterError);
                 }
-            }
-
-            if (!hasSpreadArgument && argCount < min) {
-                const diagnostic = getDiagnosticForCallNode(node, error, paramRange, argCount);
-                return related ? addRelatedInfo(diagnostic, related) : diagnostic;
-            }
-
-            if (hasRestParameter || hasSpreadArgument) {
-                spanArray = factory.createNodeArray(args);
-                if (hasSpreadArgument && argCount) {
-                    const nextArg = elementAt(args, getSpreadArgumentIndex(args) + 1) || undefined;
-                    spanArray = factory.createNodeArray(args.slice(max > argCount && nextArg ? args.indexOf(nextArg) : Math.min(max, args.length - 1)));
-                }
+                return diagnostic;
             }
             else {
-                spanArray = factory.createNodeArray(args.slice(max));
-            }
-
-            const pos = first(spanArray).pos;
-            let end = last(spanArray).end;
-            if (end === pos) {
-                end++;
+                // too long; error goes on the excess parameters
+                const errorSpan = factory.createNodeArray(args.slice(max));
+                const pos = first(errorSpan).pos;
+                let end = last(errorSpan).end;
+                if (end === pos) {
+                    end++;
+                }
+                setTextRangePosEnd(errorSpan, pos, end);
+                return createDiagnosticForNodeArray(getSourceFileOfNode(node), errorSpan, error, parameterRange, args.length);
             }
-            setTextRangePosEnd(spanArray, pos, end);
-            const diagnostic = createDiagnosticForNodeArray(
-                getSourceFileOfNode(node), spanArray, error, paramRange, argCount);
-            return related ? addRelatedInfo(diagnostic, related) : diagnostic;
         }
 
         function getTypeArgumentArityError(node: Node, signatures: readonly Signature[], typeArguments: NodeArray<TypeNode>) {

src/compiler/diagnosticMessages.json

@@ -2386,14 +2386,10 @@
         "category": "Error",
         "code": 2555
     },
-    "Expected {0} arguments, but got {1} or more.": {
+    "A spread argument must either have a tuple type or be passed to a rest parameter.": {
         "category": "Error",
         "code": 2556
     },
-    "Expected at least {0} arguments, but got {1} or more.": {
-        "category": "Error",
-        "code": 2557
-    },
     "Expected {0} type arguments, but got {1}.": {
         "category": "Error",
         "code": 2558

tests/baselines/reference/callOverload.errors.txt

@@ -1,7 +1,7 @@
 tests/cases/conformance/expressions/functionCalls/callOverload.ts(7,7): error TS2554: Expected 1 arguments, but got 4.
 tests/cases/conformance/expressions/functionCalls/callOverload.ts(8,15): error TS2554: Expected 2 arguments, but got 4.
 tests/cases/conformance/expressions/functionCalls/callOverload.ts(10,1): error TS2555: Expected at least 1 arguments, but got 0.
-tests/cases/conformance/expressions/functionCalls/callOverload.ts(11,10): error TS2557: Expected at least 1 arguments, but got 0 or more.
+tests/cases/conformance/expressions/functionCalls/callOverload.ts(11,10): error TS2556: A spread argument must either have a tuple type or be passed to a rest parameter.
 
 
 ==== tests/cases/conformance/expressions/functionCalls/callOverload.ts (4 errors) ====
@@ -24,5 +24,4 @@ tests/cases/conformance/expressions/functionCalls/callOverload.ts(11,10): error
 !!! related TS6210 tests/cases/conformance/expressions/functionCalls/callOverload.ts:3:27: An argument for 'a' was not provided.
     withRest(...n); 
              ~~~~
-!!! error TS2557: Expected at least 1 arguments, but got 0 or more.
-!!! related TS6210 tests/cases/conformance/expressions/functionCalls/callOverload.ts:3:27: An argument for 'a' was not provided.
+!!! error TS2556: A spread argument must either have a tuple type or be passed to a rest parameter.

tests/baselines/reference/callWithSpread2.errors.txt

@@ -1,5 +1,5 @@
-tests/cases/conformance/expressions/functionCalls/callWithSpread2.ts(23,13): error TS2556: Expected 1 arguments, but got 2 or more.
-tests/cases/conformance/expressions/functionCalls/callWithSpread2.ts(24,7): error TS2556: Expected 0 arguments, but got 1 or more.
+tests/cases/conformance/expressions/functionCalls/callWithSpread2.ts(23,13): error TS2556: A spread argument must either have a tuple type or be passed to a rest parameter.
+tests/cases/conformance/expressions/functionCalls/callWithSpread2.ts(24,7): error TS2556: A spread argument must either have a tuple type or be passed to a rest parameter.
 tests/cases/conformance/expressions/functionCalls/callWithSpread2.ts(27,5): error TS2345: Argument of type 'string | number' is not assignable to parameter of type 'number'.
   Type 'string' is not assignable to type 'number'.
 tests/cases/conformance/expressions/functionCalls/callWithSpread2.ts(28,5): error TS2345: Argument of type 'string' is not assignable to parameter of type 'number'.
@@ -9,10 +9,10 @@ tests/cases/conformance/expressions/functionCalls/callWithSpread2.ts(30,13): err
 tests/cases/conformance/expressions/functionCalls/callWithSpread2.ts(31,11): error TS2345: Argument of type 'string | number' is not assignable to parameter of type 'number'.
   Type 'string' is not assignable to type 'number'.
 tests/cases/conformance/expressions/functionCalls/callWithSpread2.ts(32,11): error TS2345: Argument of type 'string' is not assignable to parameter of type 'number'.
-tests/cases/conformance/expressions/functionCalls/callWithSpread2.ts(33,8): error TS2556: Expected 1-3 arguments, but got 0 or more.
-tests/cases/conformance/expressions/functionCalls/callWithSpread2.ts(34,8): error TS2556: Expected 1-3 arguments, but got 0 or more.
+tests/cases/conformance/expressions/functionCalls/callWithSpread2.ts(33,8): error TS2556: A spread argument must either have a tuple type or be passed to a rest parameter.
+tests/cases/conformance/expressions/functionCalls/callWithSpread2.ts(34,8): error TS2556: A spread argument must either have a tuple type or be passed to a rest parameter.
 tests/cases/conformance/expressions/functionCalls/callWithSpread2.ts(35,8): error TS2345: Argument of type 'number' is not assignable to parameter of type 'string'.
-tests/cases/conformance/expressions/functionCalls/callWithSpread2.ts(36,14): error TS2556: Expected 2-4 arguments, but got 1 or more.
+tests/cases/conformance/expressions/functionCalls/callWithSpread2.ts(36,14): error TS2556: A spread argument must either have a tuple type or be passed to a rest parameter.
 
 
 ==== tests/cases/conformance/expressions/functionCalls/callWithSpread2.ts (12 errors) ====
@@ -40,10 +40,10 @@ tests/cases/conformance/expressions/functionCalls/callWithSpread2.ts(36,14): err
     // extra arguments
     normal("g", ...ns)
                 ~~~~~
-!!! error TS2556: Expected 1 arguments, but got 2 or more.
+!!! error TS2556: A spread argument must either have a tuple type or be passed to a rest parameter.
     thunk(...ns)
           ~~~~~
-!!! error TS2556: Expected 0 arguments, but got 1 or more.
+!!! error TS2556: A spread argument must either have a tuple type or be passed to a rest parameter.
 
     // bad
     all(...mixed)
@@ -69,17 +69,14 @@ tests/cases/conformance/expressions/functionCalls/callWithSpread2.ts(36,14): err
 !!! error TS2345: Argument of type 'string' is not assignable to parameter of type 'number'.
     prefix(...ns) // required parameters are required
            ~~~~~
-!!! error TS2556: Expected 1-3 arguments, but got 0 or more.
-!!! related TS6210 tests/cases/conformance/expressions/functionCalls/callWithSpread2.ts:3:25: An argument for 's' was not provided.
+!!! error TS2556: A spread argument must either have a tuple type or be passed to a rest parameter.
     prefix(...mixed)
            ~~~~~~~~
-!!! error TS2556: Expected 1-3 arguments, but got 0 or more.
-!!! related TS6210 tests/cases/conformance/expressions/functionCalls/callWithSpread2.ts:3:25: An argument for 's' was not provided.
+!!! error TS2556: A spread argument must either have a tuple type or be passed to a rest parameter.
     prefix(...tuple)
            ~~~~~~~~
 !!! error TS2345: Argument of type 'number' is not assignable to parameter of type 'string'.
     prefix2("g", ...ns);
                  ~~~~~
-!!! error TS2556: Expected 2-4 arguments, but got 1 or more.
-!!! related TS6210 tests/cases/conformance/expressions/functionCalls/callWithSpread2.ts:7:37: An argument for 'n' was not provided.
+!!! error TS2556: A spread argument must either have a tuple type or be passed to a rest parameter.
 

tests/baselines/reference/callWithSpread3.errors.txt

@@ -4,12 +4,12 @@ tests/cases/conformance/expressions/functionCalls/callWithSpread3.ts(16,15): err
 tests/cases/conformance/expressions/functionCalls/callWithSpread3.ts(17,15): error TS2554: Expected 2 arguments, but got 6.
 tests/cases/conformance/expressions/functionCalls/callWithSpread3.ts(18,12): error TS2554: Expected 2 arguments, but got 3.
 tests/cases/conformance/expressions/functionCalls/callWithSpread3.ts(19,5): error TS2554: Expected 2 arguments, but got 3.
-tests/cases/conformance/expressions/functionCalls/callWithSpread3.ts(20,6): error TS2557: Expected at least 2 arguments, but got 0 or more.
+tests/cases/conformance/expressions/functionCalls/callWithSpread3.ts(20,6): error TS2556: A spread argument must either have a tuple type or be passed to a rest parameter.
 tests/cases/conformance/expressions/functionCalls/callWithSpread3.ts(21,6): error TS2345: Argument of type 'number' is not assignable to parameter of type 'string'.
-tests/cases/conformance/expressions/functionCalls/callWithSpread3.ts(22,13): error TS2557: Expected at least 2 arguments, but got 1 or more.
-tests/cases/conformance/expressions/functionCalls/callWithSpread3.ts(23,13): error TS2557: Expected at least 2 arguments, but got 2 or more.
+tests/cases/conformance/expressions/functionCalls/callWithSpread3.ts(22,6): error TS2556: A spread argument must either have a tuple type or be passed to a rest parameter.
+tests/cases/conformance/expressions/functionCalls/callWithSpread3.ts(23,6): error TS2556: A spread argument must either have a tuple type or be passed to a rest parameter.
 tests/cases/conformance/expressions/functionCalls/callWithSpread3.ts(25,7): error TS2345: Argument of type 'string' is not assignable to parameter of type 'number'.
-tests/cases/conformance/expressions/functionCalls/callWithSpread3.ts(31,13): error TS2557: Expected at least 2 arguments, but got 4 or more.
+tests/cases/conformance/expressions/functionCalls/callWithSpread3.ts(31,6): error TS2556: A spread argument must either have a tuple type or be passed to a rest parameter.
 
 
 ==== tests/cases/conformance/expressions/functionCalls/callWithSpread3.ts (12 errors) ====
@@ -46,18 +46,16 @@ tests/cases/conformance/expressions/functionCalls/callWithSpread3.ts(31,13): err
 !!! error TS2554: Expected 2 arguments, but got 3.
     fs2_(...s_); // error on ...s_
          ~~~~~
-!!! error TS2557: Expected at least 2 arguments, but got 0 or more.
-!!! related TS6210 tests/cases/conformance/expressions/functionCalls/callWithSpread3.ts:9:23: An argument for 'a' was not provided.
+!!! error TS2556: A spread argument must either have a tuple type or be passed to a rest parameter.
     fs2_(...s2n_); // error on ...s2n_
          ~~~~~~~
 !!! error TS2345: Argument of type 'number' is not assignable to parameter of type 'string'.
-    fs2_(...s_, ...s_); // error         FIXME: bad error message
-                ~~~~~
-!!! error TS2557: Expected at least 2 arguments, but got 1 or more.
-!!! related TS6210 tests/cases/conformance/expressions/functionCalls/callWithSpread3.ts:9:34: An argument for 'b' was not provided.
-    fs2_(...s_, ...s_, ...s_); // error  FIXME: worse error message
-                ~~~~~~~~~~~~
-!!! error TS2557: Expected at least 2 arguments, but got 2 or more.
+    fs2_(...s_, ...s_); // error on ...s_
+         ~~~~~
+!!! error TS2556: A spread argument must either have a tuple type or be passed to a rest parameter.
+    fs2_(...s_, ...s_, ...s_); // error on ...s_
+         ~~~~~
+!!! error TS2556: A spread argument must either have a tuple type or be passed to a rest parameter.
     // fs2n_(...s2, ...s_); //           FIXME: should be a type error
     fs2n_(...s2_); // error on ...s2_
           ~~~~~~
@@ -68,8 +66,8 @@ tests/cases/conformance/expressions/functionCalls/callWithSpread3.ts(31,13): err
     fs2_(...s2_, ...s_);
     fs2_(...s2_, ...s2_);
     fs2_(...s_, ...s2_);
-                ~~~~~~
-!!! error TS2557: Expected at least 2 arguments, but got 4 or more.
+         ~~~~~
+!!! error TS2556: A spread argument must either have a tuple type or be passed to a rest parameter.
     fs2n_(...s2n_);
     fs2n_(...s2);
     // fs2n_(...s2, ...n_); // FIXME: should compile