Add completions for introducers on literals

changelog.md

@@ -5,6 +5,7 @@ Features
 ---------
 * Dynamic terminal titles based on prompt format strings.
 * Ability to turn off the toolbar.
+* Add completions for introducers on literals.
 
 
 Bug Fixes

mycli/completion_refresher.py

@@ -160,6 +160,11 @@ def refresh_procedures(completer: SQLCompleter, executor: SQLExecute) -> None:
     completer.extend_procedures(executor.procedures())
 
 
+@refresher("character_sets")
+def refresh_character_sets(completer: SQLCompleter, executor: SQLExecute) -> None:
+    completer.extend_character_sets(executor.character_sets())
+
+
 @refresher("special_commands")
 def refresh_special(completer: SQLCompleter, executor: SQLExecute) -> None:
     completer.extend_special_commands(list(COMMANDS.keys()))

mycli/packages/completion_engine.py

@@ -399,6 +399,7 @@ def suggest_based_on_last_token(
             return [
                 {"type": "column", "tables": tables},
                 {"type": "function", "schema": []},
+                {"type": "introducer", "schema": []},
                 {"type": "alias", "aliases": aliases},
             ]
     elif (

mycli/sqlcompleter.py

@@ -1086,6 +1086,18 @@ def extend_procedures(self, procedure_data: Generator[tuple]) -> None:
                 continue
             metadata[self.dbname][elt[0]] = None
 
+    def extend_character_sets(self, character_set_data: Generator[tuple]) -> None:
+        metadata = self.dbmetadata["character_sets"]
+        if self.dbname not in metadata:
+            metadata[self.dbname] = {}
+
+        for elt in character_set_data:
+            if not elt:
+                continue
+            if not elt[0]:
+                continue
+            metadata[self.dbname][elt[0]] = None
+
     def set_dbname(self, dbname: str | None) -> None:
         self.dbname = dbname or ''
 
@@ -1099,6 +1111,7 @@ def reset_completions(self) -> None:
             "views": {},
             "functions": {},
             "procedures": {},
+            "character_sets": {},
             "enum_values": {},
         }
         self.all_completions = set(self.keywords + self.functions)
@@ -1307,6 +1320,16 @@ def get_completions(
                 )
                 completions.extend([(*x, rank) for x in procs_m])
 
+            elif suggestion['type'] == 'introducer':
+                charsets = self.populate_schema_objects(suggestion['schema'], 'character_sets')
+                introducers = [f'_{x}' for x in charsets]
+                introducers_m = self.find_matches(
+                    word_before_cursor,
+                    introducers,
+                    text_before_cursor=document.text_before_cursor,
+                )
+                completions.extend([(*x, rank) for x in introducers_m])
+
             elif suggestion["type"] == "table":
                 # If this is a select and columns are given, parse the columns and
                 # then only return tables that have one or more of the given columns.
@@ -1440,6 +1463,7 @@ def get_completions(
                     text_before_cursor=document.text_before_cursor,
                 )
                 completions.extend([(*x, rank) for x in subcommands_m])
+
             elif suggestion["type"] == "enum_value":
                 enum_values = self.populate_enum_values(
                     suggestion["tables"],

mycli/sqlexecute.py

@@ -103,6 +103,8 @@ class SQLExecute:
     procedures_query = '''SELECT ROUTINE_NAME FROM INFORMATION_SCHEMA.ROUTINES
     WHERE ROUTINE_TYPE="PROCEDURE" AND ROUTINE_SCHEMA = %s'''
 
+    character_sets_query = '''SHOW CHARACTER SET'''
+
     table_columns_query = """select TABLE_NAME, COLUMN_NAME from information_schema.columns
                                     where table_schema = %s
                                     order by table_name,ordinal_position"""
@@ -466,6 +468,20 @@ def procedures(self) -> Generator[tuple, None, None]:
             else:
                 yield from cur
 
+    def character_sets(self) -> Generator[tuple, None, None]:
+        """Yields tuples of (character_set_name, )"""
+
+        assert isinstance(self.conn, Connection)
+        with self.conn.cursor() as cur:
+            _logger.debug("Character sets Query. sql: %r", self.character_sets_query)
+            try:
+                cur.execute(self.character_sets_query)
+            except pymysql.DatabaseError as e:
+                _logger.error('No character_set completions due to %r', e)
+                yield ()
+            else:
+                yield from cur
+
     def show_candidates(self) -> Generator[tuple, None, None]:
         assert isinstance(self.conn, Connection)
         with self.conn.cursor() as cur:

test/test_completion_engine.py

@@ -21,6 +21,7 @@ def test_select_suggests_cols_with_visible_table_scope():
         {"type": "alias", "aliases": ["tabl"]},
         {"type": "column", "tables": [(None, "tabl", None)]},
         {"type": "function", "schema": []},
+        {"type": "introducer", "schema": []},
     ])
 
 
@@ -30,6 +31,7 @@ def test_select_suggests_cols_with_qualified_table_scope():
         {"type": "alias", "aliases": ["tabl"]},
         {"type": "column", "tables": [("sch", "tabl", None)]},
         {"type": "function", "schema": []},
+        {"type": "introducer", "schema": []},
     ])
 
 
@@ -53,6 +55,7 @@ def test_where_suggests_columns_functions(expression):
         {"type": "alias", "aliases": ["tabl"]},
         {"type": "column", "tables": [(None, "tabl", None)]},
         {"type": "function", "schema": []},
+        {"type": "introducer", "schema": []},
     ])
 
 
@@ -64,6 +67,7 @@ def test_where_equals_suggests_enum_values_first():
         {"type": "alias", "aliases": ["tabl"]},
         {"type": "column", "tables": [(None, "tabl", None)]},
         {"type": "function", "schema": []},
+        {"type": "introducer", "schema": []},
     ])
 
 
@@ -80,6 +84,7 @@ def test_where_in_suggests_columns(expression):
         {"type": "alias", "aliases": ["tabl"]},
         {"type": "column", "tables": [(None, "tabl", None)]},
         {"type": "function", "schema": []},
+        {"type": "introducer", "schema": []},
     ])
 
 
@@ -90,6 +95,7 @@ def test_where_equals_any_suggests_columns_or_keywords():
         {"type": "alias", "aliases": ["tabl"]},
         {"type": "column", "tables": [(None, "tabl", None)]},
         {"type": "function", "schema": []},
+        {"type": "introducer", "schema": []},
     ])
 
 
@@ -114,6 +120,7 @@ def test_select_suggests_cols_and_funcs():
         {"type": "alias", "aliases": []},
         {"type": "column", "tables": []},
         {"type": "function", "schema": []},
+        {"type": "introducer", "schema": []},
     ])
 
 
@@ -186,6 +193,7 @@ def test_col_comma_suggests_cols():
         {"type": "alias", "aliases": ["tbl"]},
         {"type": "column", "tables": [(None, "tbl", None)]},
         {"type": "function", "schema": []},
+        {"type": "introducer", "schema": []},
     ])
 
 
@@ -228,6 +236,7 @@ def test_partially_typed_col_name_suggests_col_names():
         {"type": "alias", "aliases": ["tabl"]},
         {"type": "column", "tables": [(None, "tabl", None)]},
         {"type": "function", "schema": []},
+        {"type": "introducer", "schema": []},
     ])
 
 
@@ -322,6 +331,7 @@ def test_sub_select_col_name_completion():
         {"type": "alias", "aliases": ["abc"]},
         {"type": "column", "tables": [(None, "abc", None)]},
         {"type": "function", "schema": []},
+        {"type": "introducer", "schema": []},
     ])
 
 
@@ -331,6 +341,7 @@ def test_sub_select_multiple_col_name_completion():
     assert sorted_dicts(suggestions) == sorted_dicts([
         {"type": "column", "tables": [(None, "abc", None)]},
         {"type": "function", "schema": []},
+        {"type": "introducer", "schema": []},
     ])
 
 
@@ -474,6 +485,7 @@ def test_2_statements_2nd_current():
         {"type": "alias", "aliases": ["b"]},
         {"type": "column", "tables": [(None, "b", None)]},
         {"type": "function", "schema": []},
+        {"type": "introducer", "schema": []},
     ])
 
     # Should work even if first statement is invalid
@@ -498,6 +510,7 @@ def test_2_statements_1st_current():
         {"type": "alias", "aliases": ["a"]},
         {"type": "column", "tables": [(None, "a", None)]},
         {"type": "function", "schema": []},
+        {"type": "introducer", "schema": []},
     ])
 
 
@@ -514,6 +527,7 @@ def test_3_statements_2nd_current():
         {"type": "alias", "aliases": ["b"]},
         {"type": "column", "tables": [(None, "b", None)]},
         {"type": "function", "schema": []},
+        {"type": "introducer", "schema": []},
     ])
 
 

test/test_completion_refresher.py

@@ -30,6 +30,7 @@ def test_ctor(refresher):
         "users",
         "functions",
         "procedures",
+        "character_sets",
         "special_commands",
         "show_commands",
         "keywords",

test/test_smart_completion_public_schema_only.py

@@ -125,6 +125,16 @@ def test_select_star(completer, complete_event):
     assert list(result) == list(map(Completion, completer.keywords))
 
 
+def test_introducer_completion(completer, complete_event):
+    completer.extend_character_sets([('latin1',), ('utf8mb4',)])
+    text = 'SELECT _'
+    position = len(text)
+    result = list(completer.get_completions(Document(text=text, cursor_position=position), complete_event))
+    result_text = [item.text for item in result]
+    assert '_latin1' in result_text
+    assert '_utf8mb4' in result_text
+
+
 def test_table_completion(completer, complete_event):
     text = "SELECT * FROM "
     position = len(text)