feat(grammar): RAISE, ASSERT, EXCEPTION handlers and GET DIAGNOSTICS

grammar/keywords.js

@@ -251,6 +251,31 @@ export default {
   keyword_inout: _ => make_keyword("inout"),
   keyword_variadic: _ => make_keyword("variadic"),
   keyword_ordinality: _ => make_keyword("ordinality"),
+  keyword_loop: _ => make_keyword("loop"),
+  keyword_exit: _ => make_keyword("exit"),
+  keyword_continue: _ => make_keyword("continue"),
+  keyword_elsif: _ => make_keyword("elsif"),
+  keyword_elseif: _ => make_keyword("elseif"),
+  keyword_reverse: _ => make_keyword("reverse"),
+  keyword_foreach: _ => make_keyword("foreach"),
+  keyword_slice: _ => make_keyword("slice"),
+  keyword_raise: _ => make_keyword("raise"),
+  keyword_exception: _ => make_keyword("exception"),
+  keyword_debug: _ => make_keyword("debug"),
+  keyword_log: _ => make_keyword("log"),
+  keyword_info: _ => make_keyword("info"),
+  keyword_notice: _ => make_keyword("notice"),
+  keyword_warning: _ => make_keyword("warning"),
+  keyword_sqlstate: _ => make_keyword("sqlstate"),
+  keyword_message: _ => make_keyword("message"),
+  keyword_detail: _ => make_keyword("detail"),
+  keyword_hint: _ => make_keyword("hint"),
+  keyword_errcode: _ => make_keyword("errcode"),
+  keyword_datatype: _ => make_keyword("datatype"),
+  keyword_assert: _ => make_keyword("assert"),
+  keyword_get: _ => make_keyword("get"),
+  keyword_stacked: _ => make_keyword("stacked"),
+  keyword_diagnostics: _ => make_keyword("diagnostics"),
 
   keyword_session: _ => make_keyword("session"),
   keyword_isolation: _ => make_keyword("isolation"),

grammar/statements/control-flow.js

@@ -0,0 +1,145 @@
+import { comma_list, paren_list } from "../helpers.js";
+
+// Procedural statements shared by PL/pgSQL and PL/SQL. They are only reachable
+// from a function or procedure body and from a BEGIN ... END block, never from
+// a plain top-level statement.
+export default {
+
+  _procedural_statement: $ => choice(
+    alias($._variable_assignment, $.assignment),
+    $.if_statement,
+    $.case_statement,
+    $.loop_statement,
+    $.exit_statement,
+    $.continue_statement,
+    $.keyword_null,
+    $.block,
+    $.raise_statement,
+    $.assert_statement,
+    $.get_diagnostics,
+  ),
+
+  _procedural_statements: $ => repeat1(
+    seq(
+      $._function_body_statement,
+      ';',
+    ),
+  ),
+
+  _variable_assignment: $ => seq(
+    field('left', alias($._qualified_field, $.field)),
+    choice(':=', '='),
+    field('right', $._expression),
+  ),
+
+  label: $ => seq('<<', $.identifier, '>>'),
+
+  if_statement: $ => seq(
+    $.keyword_if,
+    $._expression,
+    $.keyword_then,
+    optional($._procedural_statements),
+    repeat(
+      seq(
+        choice($.keyword_elsif, $.keyword_elseif),
+        $._expression,
+        $.keyword_then,
+        optional($._procedural_statements),
+      ),
+    ),
+    optional(
+      seq(
+        $.keyword_else,
+        optional($._procedural_statements),
+      ),
+    ),
+    $.keyword_end,
+    $.keyword_if,
+  ),
+
+  case_statement: $ => seq(
+    $.keyword_case,
+    optional($._expression),
+    repeat1(
+      seq(
+        $.keyword_when,
+        comma_list($._expression, true),
+        $.keyword_then,
+        optional($._procedural_statements),
+      ),
+    ),
+    optional(
+      seq(
+        $.keyword_else,
+        optional($._procedural_statements),
+      ),
+    ),
+    $.keyword_end,
+    $.keyword_case,
+  ),
+
+  loop_statement: $ => seq(
+    optional($.label),
+    optional(
+      choice(
+        seq($.keyword_while, $._expression),
+        seq(
+          $.keyword_for,
+          comma_list($.identifier, true),
+          $.keyword_in,
+          choice(
+            $._for_range,
+            $.statement,
+            // a bound cursor, with or without arguments
+            alias($._qualified_field, $.field),
+            $.invocation,
+          ),
+        ),
+        seq(
+          $.keyword_foreach,
+          comma_list($.identifier, true),
+          optional(seq($.keyword_slice, $._natural_number)),
+          $.keyword_in,
+          $.keyword_array,
+          $._expression,
+        ),
+      ),
+    ),
+    $.keyword_loop,
+    optional($._procedural_statements),
+    $.keyword_end,
+    $.keyword_loop,
+    optional($.identifier),
+  ),
+
+  _for_range: $ => seq(
+    optional($.keyword_reverse),
+    choice(
+      alias($._range_start_integer, $.literal),
+      $._expression,
+    ),
+    '..',
+    $._expression,
+    optional(seq($.keyword_by, $._expression)),
+  ),
+
+  // `1..10` would otherwise lex as the two decimals `1.` and `.10`; a higher
+  // lexical precedence stops the integer from absorbing the dot.
+  _range_start_integer: $ => seq(
+    optional(choice('-', '+')),
+    token(prec(1, /\d+/)),
+  ),
+
+  exit_statement: $ => seq(
+    $.keyword_exit,
+    optional($.identifier),
+    optional(seq($.keyword_when, $._expression)),
+  ),
+
+  continue_statement: $ => seq(
+    $.keyword_continue,
+    optional($.identifier),
+    optional(seq($.keyword_when, $._expression)),
+  ),
+
+};

grammar/statements/create-function.js

@@ -78,7 +78,7 @@ export default {
 
   _function_return: $ => seq(
     $.keyword_return,
-    $._expression,
+    optional($._expression),
   ),
 
   function_declaration: $ => seq(
@@ -101,6 +101,7 @@ export default {
   _function_body_statement: $ => choice(
     $.statement,
     $._function_return,
+    $._procedural_statement,
   ),
 
   _tsql_function_body_statement: $ => seq(
@@ -127,17 +128,13 @@ export default {
     seq(
       $.keyword_begin,
       $.keyword_atomic,
-      repeat1(
-        seq(
-          $._function_body_statement,
-          ';',
-        ),
-      ),
+      $._procedural_statements,
       $.keyword_end,
     ),
     seq(
       $.keyword_as,
       alias($._dollar_quoted_string_start_tag, $.dollar_quote),
+      optional($.label),
       optional(
         seq(
           $.keyword_declare,
@@ -147,12 +144,8 @@ export default {
         ),
       ),
       $.keyword_begin,
-      repeat1(
-        seq(
-          $._function_body_statement,
-          ';',
-        ),
-      ),
+      $._procedural_statements,
+      optional($._exception_handlers),
       $.keyword_end,
       optional(';'),
       alias($._dollar_quoted_string_end_tag, $.dollar_quote),
@@ -170,7 +163,12 @@ export default {
     seq(
       $.keyword_as,
       alias($._dollar_quoted_string_start_tag, $.dollar_quote),
-      $._function_body_statement,
+      // a single SQL statement, e.g. a `language sql` body; a procedural
+      // statement here would be ambiguous with the `begin ... end` form
+      choice(
+        $.statement,
+        $._function_return,
+      ),
       optional(';'),
       alias($._dollar_quoted_string_end_tag, $.dollar_quote),
     ),

grammar/statements/create-procedure.js

@@ -31,18 +31,14 @@ export default {
     seq(
       $.keyword_begin,
       $.keyword_atomic,
-      repeat1(
-        seq(
-          $._function_body_statement,
-          ';',
-        ),
-      ),
+      $._procedural_statements,
       $.keyword_end,
     ),
     // Dollar-quoted with optional DECLARE (PostgreSQL)
     seq(
       $.keyword_as,
       alias($._dollar_quoted_string_start_tag, $.dollar_quote),
+      optional($.label),
       optional(
         seq(
           $.keyword_declare,
@@ -52,12 +48,8 @@ export default {
         ),
       ),
       $.keyword_begin,
-      repeat1(
-        seq(
-          $._function_body_statement,
-          ';',
-        ),
-      ),
+      $._procedural_statements,
+      optional($._exception_handlers),
       $.keyword_end,
       optional(';'),
       alias($._dollar_quoted_string_end_tag, $.dollar_quote),
@@ -77,7 +69,12 @@ export default {
     seq(
       $.keyword_as,
       alias($._dollar_quoted_string_start_tag, $.dollar_quote),
-      $._function_body_statement,
+      // a single SQL statement, e.g. a `language sql` body; a procedural
+      // statement here would be ambiguous with the `begin ... end` form
+      choice(
+        $.statement,
+        $._function_return,
+      ),
       optional(';'),
       alias($._dollar_quoted_string_end_tag, $.dollar_quote),
     ),

grammar/statements/error-handling.js

@@ -0,0 +1,90 @@
+import { comma_list } from "../helpers.js";
+
+// RAISE, ASSERT, EXCEPTION handlers and GET DIAGNOSTICS, as used by PL/pgSQL
+// and PL/SQL bodies.
+export default {
+
+  raise_statement: $ => seq(
+    $.keyword_raise,
+    optional(
+      choice(
+        $.keyword_debug,
+        $.keyword_log,
+        $.keyword_info,
+        $.keyword_notice,
+        $.keyword_warning,
+        $.keyword_exception,
+      ),
+    ),
+    optional(
+      choice(
+        seq($.keyword_sqlstate, alias($._literal_string, $.literal)),
+        // a format string with its arguments, or a bare condition name
+        comma_list($._expression, true),
+      ),
+    ),
+    optional(
+      seq(
+        $.keyword_using,
+        comma_list($.raise_option, true),
+      ),
+    ),
+  ),
+
+  raise_option: $ => seq(
+    choice(
+      $.keyword_message,
+      $.keyword_detail,
+      $.keyword_hint,
+      $.keyword_errcode,
+      $.keyword_column,
+      $.keyword_constraint,
+      $.keyword_datatype,
+      $.keyword_table,
+      $.keyword_schema,
+    ),
+    choice('=', ':='),
+    $._expression,
+  ),
+
+  assert_statement: $ => seq(
+    $.keyword_assert,
+    $._expression,
+    optional(seq(',', $._expression)),
+  ),
+
+  // `exception when ... then ...`, at the end of a block or body
+  _exception_handlers: $ => seq(
+    $.keyword_exception,
+    repeat1($.exception_handler),
+  ),
+
+  exception_handler: $ => seq(
+    $.keyword_when,
+    $._exception_condition,
+    repeat(seq($.keyword_or, $._exception_condition)),
+    $.keyword_then,
+    optional($._procedural_statements),
+  ),
+
+  _exception_condition: $ => choice(
+    $.keyword_others,
+    seq($.keyword_sqlstate, alias($._literal_string, $.literal)),
+    $.identifier,
+  ),
+
+  get_diagnostics: $ => seq(
+    $.keyword_get,
+    optional(choice($.keyword_current, $.keyword_stacked)),
+    $.keyword_diagnostics,
+    comma_list(
+      seq(
+        alias($._qualified_field, $.field),
+        choice('=', ':='),
+        $.identifier,
+      ),
+      true,
+    ),
+  ),
+
+};