parser: fix cast validation issue

crates/squawk_syntax/src/postgresql.ungram

@@ -70,7 +70,7 @@ CallExpr =
   Expr ArgList
 
 CastExpr =
-  Expr ColonColon Type
+  Expr (ColonColon? | 'as') Type
 
 ArrayExpr =
   'array' '[' (Expr (',' Expr)*) ']'

crates/squawk_syntax/src/snapshots/squawk_syntax__test__alter_table_ok_validation.snap

@@ -0,0 +1,134 @@
+---
+source: crates/squawk_syntax/src/test.rs
+input_file: crates/squawk_syntax/test_data/validation/alter_table_ok.sql
+---
+SOURCE_FILE@0..470
+  COMMENT@0..66 "-- regression test fo ..."
+  WHITESPACE@66..67 "\n"
+  ALTER_TABLE@67..243
+    ALTER_KW@67..72 "alter"
+    WHITESPACE@72..73 " "
+    TABLE_KW@73..78 "table"
+    WHITESPACE@78..79 " "
+    RELATION_NAME@79..92
+      PATH@79..92
+        PATH@79..85
+          PATH_SEGMENT@79..85
+            NAME_REF@79..85
+              IDENT@79..85 "public"
+        DOT@85..86 "."
+        PATH_SEGMENT@86..92
+          NAME_REF@86..92
+            IDENT@86..92 "widget"
+    WHITESPACE@92..95 "\n  "
+    ADD_CONSTRAINT@95..243
+      ADD_KW@95..98 "add"
+      WHITESPACE@98..99 " "
+      CHECK_CONSTRAINT@99..233
+        CONSTRAINT_KW@99..109 "constraint"
+        WHITESPACE@109..110 " "
+        NAME@110..136
+          IDENT@110..136 "widget_config_schema_ ..."
+        WHITESPACE@136..137 " "
+        CHECK_KW@137..142 "check"
+        WHITESPACE@142..143 " "
+        L_PAREN@143..144 "("
+        WHITESPACE@144..149 "\n    "
+        CALL_EXPR@149..229
+          FIELD_EXPR@149..178
+            NAME_REF@149..155
+              IDENT@149..155 "checks"
+            DOT@155..156 "."
+            NAME_REF@156..178
+              IDENT@156..178 "is_widget_config_valid"
+          ARG_LIST@178..229
+            L_PAREN@178..179 "("
+            CAST_EXPR@179..220
+              LITERAL@179..187
+                STRING@179..187 "'widget'"
+              COLON_COLON@187..189
+                COLON@187..188 ":"
+                COLON@188..189 ":"
+              FIELD_EXPR@189..220
+                NAME_REF@189..201
+                  IDENT@189..201 "custom_types"
+                DOT@201..202 "."
+                NAME_REF@202..220
+                  IDENT@202..220 "widget_schema_type"
+            COMMA@220..221 ","
+            WHITESPACE@221..222 " "
+            NAME_REF@222..228
+              IDENT@222..228 "config"
+            R_PAREN@228..229 ")"
+        WHITESPACE@229..232 "\n  "
+        R_PAREN@232..233 ")"
+      WHITESPACE@233..234 " "
+      NOT_VALID@234..243
+        NOT_KW@234..237 "not"
+        WHITESPACE@237..238 " "
+        VALID_KW@238..243 "valid"
+  SEMICOLON@243..244 ";"
+  WHITESPACE@244..246 "\n\n"
+  ALTER_TABLE@246..469
+    ALTER_KW@246..251 "alter"
+    WHITESPACE@251..252 " "
+    TABLE_KW@252..257 "table"
+    WHITESPACE@257..258 " "
+    RELATION_NAME@258..280
+      PATH@258..280
+        PATH@258..264
+          PATH_SEGMENT@258..264
+            NAME_REF@258..264
+              IDENT@258..264 "public"
+        DOT@264..265 "."
+        PATH_SEGMENT@265..280
+          NAME_REF@265..280
+            IDENT@265..280 "widget_instance"
+    WHITESPACE@280..283 "\n  "
+    ADD_CONSTRAINT@283..469
+      ADD_KW@283..286 "add"
+      WHITESPACE@286..287 " "
+      CHECK_CONSTRAINT@287..459
+        CONSTRAINT_KW@287..297 "constraint"
+        WHITESPACE@297..298 " "
+        NAME@298..343
+          IDENT@298..343 "widget_instance_confi ..."
+        WHITESPACE@343..344 " "
+        CHECK_KW@344..349 "check"
+        WHITESPACE@349..350 " "
+        L_PAREN@350..351 "("
+        WHITESPACE@351..356 "\n    "
+        CALL_EXPR@356..455
+          FIELD_EXPR@356..385
+            NAME_REF@356..362
+              IDENT@356..362 "checks"
+            DOT@362..363 "."
+            NAME_REF@363..385
+              IDENT@363..385 "is_widget_config_valid"
+          ARG_LIST@385..455
+            L_PAREN@385..386 "("
+            CAST_EXPR@386..436
+              LITERAL@386..403
+                STRING@386..403 "'widget_instance'"
+              COLON_COLON@403..405
+                COLON@403..404 ":"
+                COLON@404..405 ":"
+              FIELD_EXPR@405..436
+                NAME_REF@405..417
+                  IDENT@405..417 "custom_types"
+                DOT@417..418 "."
+                NAME_REF@418..436
+                  IDENT@418..436 "widget_schema_type"
+            COMMA@436..437 ","
+            WHITESPACE@437..438 " "
+            NAME_REF@438..454
+              IDENT@438..454 "config_overrides"
+            R_PAREN@454..455 ")"
+        WHITESPACE@455..458 "\n  "
+        R_PAREN@458..459 ")"
+      WHITESPACE@459..460 " "
+      NOT_VALID@460..469
+        NOT_KW@460..463 "not"
+        WHITESPACE@463..464 " "
+        VALID_KW@464..469 "valid"
+  WHITESPACE@469..470 "\n"

crates/squawk_syntax/src/test.rs

@@ -43,9 +43,17 @@ fn syntaxtest(fixture: Fixture<&str>) {
       assert_snapshot!(format!("{}_{}", test_name, parent_dir), buffer);
     });
 
-    assert_ne!(
-        errors.len(),
-        0,
-        "tests defined in the `syntax/test_data` must have errors."
-    );
+    if test_name.ends_with("_ok") {
+        assert_eq!(
+            errors.len(),
+            0,
+            "tests defined in the `syntax/test_data` ending with `_ok` can't have errors."
+        );
+    } else {
+        assert_ne!(
+            errors.len(),
+            0,
+            "tests defined in the `syntax/test_data` must have errors."
+        );
+    }
 }

crates/squawk_syntax/src/validation.rs

@@ -18,7 +18,6 @@ pub(crate) fn validate(root: &SyntaxNode, errors: &mut Vec<SyntaxError>) {
                 ast::PrefixExpr(it) => validate_prefix_expr(it, errors),
                 ast::ArrayExpr(it) => validate_array_expr(it, errors),
                 ast::DropAggregate(it) => validate_drop_aggregate(it, errors),
-                ast::CallExpr(it) => validate_call_expr(it, errors),
                 ast::JoinExpr(it) => validate_join_expr(it, errors),
                 ast::Literal(it) => validate_literal(it, errors),
                 ast::NonStandardParam(it) => validate_non_standard_param(it, errors),
@@ -28,20 +27,6 @@ pub(crate) fn validate(root: &SyntaxNode, errors: &mut Vec<SyntaxError>) {
     }
 }
 
-fn validate_call_expr(it: ast::CallExpr, acc: &mut Vec<SyntaxError>) {
-    let Some(arg_list) = it.arg_list() else {
-        return;
-    };
-    for arg in arg_list.args() {
-        if let ast::Expr::CastExpr(cast_expr) = &arg {
-            acc.push(SyntaxError::new(
-                "Invalid cast. Use `cast`, `treat`, or `::` instead.",
-                cast_expr.syntax().text_range(),
-            ));
-        }
-    }
-}
-
 fn validate_create_table(it: ast::CreateTable, acc: &mut Vec<SyntaxError>) {
     let Some(arg_list) = it.table_arg_list() else {
         return;

crates/squawk_syntax/test_data/validation/alter_table_ok.sql

@@ -0,0 +1,10 @@
+-- regression test for https://github.com/sbdchd/squawk/issues/597
+alter table public.widget
+  add constraint widget_config_schema_check check (
+    checks.is_widget_config_valid('widget'::custom_types.widget_schema_type, config)
+  ) not valid;
+
+alter table public.widget_instance
+  add constraint widget_instance_config_overrides_schema_check check (
+    checks.is_widget_config_valid('widget_instance'::custom_types.widget_schema_type, config_overrides)
+  ) not valid