Add support for COMMIT statement

This commit allows us to parse the the `COMMIT` / `END` statements.

Author: bfad

README.md

@@ -203,7 +203,7 @@ SQLite works with a grammar of _167_ token types, _136_ of which are keywords. T
 - [ ] `analyze_stmt`
 - [ ] `attach_stmt`
 - [ ] `begin_stmt`
-- [ ] `commit_stmt`
+- [x] `commit_stmt`
 - [x] `create_table_stmt`
 - [ ] `create_index_stmt`
 - [ ] `create_trigger_stmt`

lib/plume.rb

@@ -26,6 +26,7 @@ module Plume
 	autoload :ColumnDefinition, "plume/ast/column_definition"
 	autoload :ColumnName, "plume/ast/column_name"
 	autoload :ColumnType, "plume/ast/column_type"
+	autoload :CommitStatement, "plume/ast/commit_statement"
 	autoload :ConflictClause, "plume/ast/conflict_clause"
 	autoload :CreateTableStatement, "plume/ast/create_table_statement"
 	autoload :CrossJoinOperator, "plume/ast/cross_join_operator"

lib/plume/ast/commit_statement.rb

@@ -0,0 +1,15 @@
+# frozen_string_literal: true
+
+module Plume
+	# **[SQLite Docs](https://www.sqlite.org/lang_transaction.html)**
+	#
+	# ```sql
+	# commmit
+	# ```
+	class CommitStatement < Node
+		token :commit_kw
+		token :transaction_kw
+
+		def self.concrete(*, commit_kw:, transaction_kw:, **) = super
+	end
+end

lib/plume/parser.rb

@@ -596,6 +596,31 @@ def select_stmt
 			# end
 		end
 
+		def commit_stmt
+			#
+				# Relevant `parse.y` grammar rules:
+				# cmd ::= COMMIT|END(X) trans_opt.   {sqlite3EndTransaction(pParse,@X);}
+				#
+				# Syntax diagram:
+				#   ◯─▶┬─▶{ COMMIT }┬─▶─┬──▶{ TRANSACTION }─┬─▶◯
+				#      ├▶{ End }──▶─┤   ├─────────▶─────────┤
+
+				# Simplified grammar:
+				#   COMMIT [TRANSACTION] | END [TRANSACTION]
+				#
+				# Relevant SQLite documentation:
+				#   - https://www.sqlite.org/lang_transaction.html
+			#
+			commit_kw = require_one_of :COMMIT, :END
+			transaction_kw = maybe :TRANSACTION
+
+			CommitStatement.concrete(
+				full_source:      @lexer.sql,
+				commit_kw:        Token::Keyword(commit_kw),
+				transaction_kw:  Token::Keyword(transaction_kw),
+			)
+		end
+
 		# ---------- Clauses ----------
 
 		def expression(min_precedence = 0)
@@ -2818,4 +2843,4 @@ def error!(token, value, expected)
 			throw :ERROR, ErrorMessage.new(msg)
 		end
 	end
-end
+end

test/commit.test.rb

@@ -0,0 +1,37 @@
+# frozen_string_literal: true
+
+test "commit" do
+	node = parse_stmt(<<~SQL)
+		COMMIT;
+	SQL
+
+	assert_equal node.commit_kw_val, "COMMIT"
+	assert_equal node.transaction_kw_val, nil
+end
+
+test "commit transaction" do
+	node = parse_stmt(<<~SQL)
+		COMMIT TRANSACTION;
+	SQL
+
+	assert_equal node.commit_kw_val, "COMMIT"
+	assert_equal node.transaction_kw_val, "TRANSACTION"
+end
+
+test "end" do
+	node = parse_stmt(<<~SQL)
+		end;
+	SQL
+
+	assert_equal node.commit_kw_val, "end"
+	assert_equal node.transaction_kw_val, nil
+end
+
+test "end transaction" do
+	node = parse_stmt(<<~SQL)
+		end transaction;
+	SQL
+
+	assert_equal node.commit_kw_val, "end"
+	assert_equal node.transaction_kw_val, "transaction"
+end