[Parser] Add support for parsing nested function calls

src/lpython/parser/parser.yy

@@ -805,6 +805,15 @@ function_call
     | primary "(" keyword_items comma_opt ")" { $$ = CALL_03($1, $3, @$); }
     | primary "(" expr comp_for_items ")" {
         $$ = CALL_04($1, GENERATOR_EXPR($3, $4, @$), @$); }
+    | function_call "(" expr_list_opt ")" { $$ = CALL_01($1, $3, @$); }
+    | function_call "(" expr_list "," ")" { $$ = CALL_01($1, $3, @$); }
+    | function_call "(" expr_list "," keyword_items comma_opt ")" {
+        $$ = CALL_02($1, $3, $5, @$); }
+    | function_call "(" keyword_items "," expr_list comma_opt ")" {
+        $$ = CALL_02($1, $5, $3, @$); }
+    | function_call "(" keyword_items comma_opt ")" { $$ = CALL_03($1, $3, @$); }
+    | function_call "(" expr comp_for_items ")" {
+        $$ = CALL_04($1, GENERATOR_EXPR($3, $4, @$), @$); }
     ;
 
 subscription

tests/parser/statements2.py

@@ -0,0 +1,3 @@
+getattr(x, y)(a, b,)(5, a=a, b=0)
+func(a, _op)(s)
+test()()

tests/reference/ast_new-statements2-c4cdc5f.json

@@ -0,0 +1,13 @@
+{
+    "basename": "ast_new-statements2-c4cdc5f",
+    "cmd": "lpython --show-ast --new-parser --no-color {infile} -o {outfile}",
+    "infile": "tests/parser/statements2.py",
+    "infile_hash": "2b7785ebfba06ec07891cd50f2e66555218192c04730e11574f8db4e",
+    "outfile": null,
+    "outfile_hash": null,
+    "stdout": "ast_new-statements2-c4cdc5f.stdout",
+    "stdout_hash": "96a46e9c67a48061b16c6486fa0df0bb587c38fff1a6c2e77ae0459f",
+    "stderr": null,
+    "stderr_hash": null,
+    "returncode": 0
+}

tests/reference/ast_new-statements2-c4cdc5f.stdout

@@ -0,0 +1 @@
+(Module [(Expr (Call (Call (Call (Name getattr Load) [(Name x Load) (Name y Load)] []) [(Name a Load) (Name b Load)] []) [(ConstantInt 5 ())] [(a (Name a Load)) (b (ConstantInt 0 ()))])) (Expr (Call (Call (Name func Load) [(Name a Load) (Name _op Load)] []) [(Name s Load)] [])) (Expr (Call (Call (Name test Load) [] []) [] []))] [])

tests/tests.toml

@@ -411,6 +411,10 @@ ast_new = true
 filename = "parser/statements1.py"
 ast_new = true
 
+[[test]]
+filename = "parser/statements2.py"
+ast_new = true
+
 [[test]]
 filename = "parser/yield.py"
 ast_new = true