[ruby/prism] Fix and reuse pm_call_node_index_p

Fix https://github.com/ruby/prism/pull/1925
Fix https://github.com/ruby/prism/pull/1927

Previously pm_call_node_index_p does not check about a block argument
correctly and is not used in parse_write to check an index call node.

This commit fixes these problems.

https://github.com/ruby/prism/commit/92bab044ff

prism/prism.c

@@ -1840,8 +1840,8 @@ pm_call_node_variable_call_p(pm_call_node_t *node) {
 }
 
 /**
- * Returns whether or not this call is to the [] method in the index form (as
- * opposed to `foo.[]`).
+ * Returns whether or not this call is to the [] method in the index form without a block (as
+ * opposed to `foo.[]` and `foo[] { }`).
  */
 static inline bool
 pm_call_node_index_p(pm_call_node_t *node) {
@@ -1849,7 +1849,8 @@ pm_call_node_index_p(pm_call_node_t *node) {
         (node->call_operator_loc.start == NULL) &&
         (node->message_loc.start != NULL) &&
         (node->message_loc.start[0] == '[') &&
-        (node->message_loc.end[-1] == ']')
+        (node->message_loc.end[-1] == ']') &&
+        (node->block == NULL || PM_NODE_TYPE_P(node->block, PM_BLOCK_ARGUMENT_NODE))
     );
 }
 
@@ -10827,13 +10828,7 @@ parse_write(pm_parser_t *parser, pm_node_t *target, pm_token_t *operator, pm_nod
             // If there is no call operator and the message is "[]" then this is
             // an aref expression, and we can transform it into an aset
             // expression.
-            if (
-                (call->call_operator_loc.start == NULL) &&
-                (call->message_loc.start != NULL) &&
-                (call->message_loc.start[0] == '[') &&
-                (call->message_loc.end[-1] == ']') &&
-                (call->block == NULL)
-            ) {
+            if (pm_call_node_index_p(call)) {
                 if (call->arguments == NULL) {
                     call->arguments = pm_arguments_node_create(parser);
                 }

test/prism/errors_test.rb

@@ -1256,6 +1256,33 @@ module Prism
       ]
     end
 
+    def test_index_call_with_block_and_write
+      source = "foo[1] {} &&= 1"
+      assert_errors expression(source), source, [
+        ["Unexpected write target", 0..9],
+        ["Unexpected operator after a call with arguments", 10..13],
+        ["Unexpected operator after a call with a block", 10..13]
+      ]
+    end
+
+    def test_index_call_with_block_or_write
+      source = "foo[1] {} ||= 1"
+      assert_errors expression(source), source, [
+        ["Unexpected write target", 0..9],
+        ["Unexpected operator after a call with arguments", 10..13],
+        ["Unexpected operator after a call with a block", 10..13]
+      ]
+    end
+
+    def test_index_call_with_block_operator_write
+      source = "foo[1] {} += 1"
+      assert_errors expression(source), source, [
+        ["Unexpected write target", 0..9],
+        ["Unexpected operator after a call with arguments", 10..12],
+        ["Unexpected operator after a call with a block", 10..12]
+      ]
+    end
+
     def test_writing_numbered_parameter
       assert_errors expression("-> { _1 = 0 }"), "-> { _1 = 0 }", [
         ["_1 is reserved for a numbered parameter", 5..7]

test/prism/fixtures/arrays.txt

@@ -81,6 +81,14 @@ foo[bar] = baz
 
 %w[\C:]
 
+foo[&bar] = 1
+
+foo.foo[&bar] = 1
+
+def foo(&)
+  bar[&] = 1
+end
+
 foo[] += 1
 
 foo[] ||= 1