fix #482: support anti, semi, positional, asof joins

CHANGELOG.md

@@ -12,6 +12,7 @@ All notable changes to this project will be documented in this file.
 
 -   `any()` and `all()` will no longer get spaces between the function name and the parenthesis, unless they are a part of a `like any ()` or `like all ()` operator ([#483](https://github.com/tconbeer/sqlfmt/issues/483) - thank you [@damirbk](https://github.com/damirbk)!).
 -   Snowflake's `//` comment markers are now parsed as comments and rewritten to `--` on formatting ([#468](https://github.com/tconbeer/sqlfmt/issues/468) - thank you [@nilsonavp](https://github.com/nilsonavp)!).
+-   DuckDB's `semi`, `anti`, `positional`, and `asof` joins are now supported. ([#482](https://github.com/tconbeer/sqlfmt/issues/482)).
 
 ## [0.19.2] - 2023-07-31
 

src/sqlfmt/rules/__init__.py

@@ -122,10 +122,8 @@
             ),
             r"delete\s+from",
             r"from",
-            (
-                r"(natural\s+)?"
-                r"((inner|cross|((left|right|full)(\s+outer)?))\s+)?join"
-            ),
+            r"((cross|positional|semi|anti)\s+)?join",
+            (r"((natural|asof)\s+)?" r"((inner|(left|right|full)(\s+outer)?)\s+)?join"),
             # this is the USING following DELETE, not the join operator
             # (see above)
             r"using",

tests/data/unformatted/129_duckdb_joins.sql

@@ -0,0 +1,86 @@
+-- Source https://duckdb.org/docs/sql/query_syntax/from.html
+-- Copyright DuckDB Foundation.
+
+-- return a list of cars that have a valid region.
+SELECT cars.name, cars.manufacturer 
+FROM cars SEMI JOIN region
+ON cars.region = region.id;
+-- return a list of cars with no recorded safety data.
+SELECT cars.name, cars.manufacturer
+FROM cars ANTI JOIN safety_data
+ON cars.safety_report_id = safety_data.report_id;
+SELECT *
+FROM range(3) t(i), LATERAL (SELECT i + 1) t2(j);
+SELECT *
+FROM generate_series(0, 1) t(i), LATERAL (SELECT i + 10 UNION ALL SELECT i + 100) t2(j);
+CREATE TABLE t1 AS SELECT * FROM range(3) t(i), LATERAL (SELECT i + 1) t2(j);
+SELECT * FROM t1, LATERAL (SELECT i + j) t2(k);
+-- treat two data frames as a single table
+SELECT df1.*, df2.*
+FROM df1 POSITIONAL JOIN df2;
+-- attach prices to stock trades
+SELECT t.*, p.price
+FROM trades t ASOF JOIN prices p 
+  ON t.symbol = p.symbol AND t.created_at >= p.created_at;
+  -- attach prices or NULLs to stock trades
+SELECT *
+FROM trades t ASOF LEFT JOIN prices p 
+  ON t.symbol = p.symbol AND t.created_at >= p.created_at;
+SELECT *
+FROM trades t ASOF JOIN prices p USING (symbol, created_at);
+-- Returns symbol, trades.created_at, price (but NOT prices.created_at)
+SELECT t.symbol, t.created_at AS trade_when, p.created_at AS price_when, price
+FROM trades t ASOF LEFT JOIN prices p USING (symbol, created_at);
+)))))__SQLFMT_OUTPUT__(((((
+-- Source https://duckdb.org/docs/sql/query_syntax/from.html
+-- Copyright DuckDB Foundation.
+-- return a list of cars that have a valid region.
+select cars.name, cars.manufacturer
+from cars
+semi join region on cars.region = region.id
+;
+-- return a list of cars with no recorded safety data.
+select cars.name, cars.manufacturer
+from cars
+anti join safety_data on cars.safety_report_id = safety_data.report_id
+;
+select *
+from range(3) t(i), lateral(select i + 1) t2(j)
+;
+select *
+from
+    generate_series(0, 1) t(i),
+    lateral(
+        select i + 10
+        union all
+        select i + 100
+    ) t2(j)
+;
+CREATE TABLE t1 AS SELECT * FROM range(3) t(i), LATERAL (SELECT i + 1) t2(j);
+select *
+from t1, lateral(select i + j) t2(k)
+;
+-- treat two data frames as a single table
+select df1.*, df2.*
+from df1
+positional join df2
+;
+-- attach prices to stock trades
+select t.*, p.price
+from trades t
+asof join prices p on t.symbol = p.symbol and t.created_at >= p.created_at
+;
+-- attach prices or NULLs to stock trades
+select *
+from trades t
+asof left join prices p on t.symbol = p.symbol and t.created_at >= p.created_at
+;
+select *
+from trades t
+asof join prices p using (symbol, created_at)
+;
+-- Returns symbol, trades.created_at, price (but NOT prices.created_at)
+select t.symbol, t.created_at as trade_when, p.created_at as price_when, price
+from trades t
+asof left join prices p using (symbol, created_at)
+;

tests/functional_tests/test_general_formatting.py

@@ -45,6 +45,7 @@
         "unformatted/126_blank_lines.sql",
         "unformatted/127_more_comments.sql",
         "unformatted/128_double_slash_comments.sql",
+        "unformatted/129_duckdb_joins.sql",
         "unformatted/200_base_model.sql",
         "unformatted/201_basic_snapshot.sql",
         "unformatted/202_unpivot_macro.sql",

tests/unit_tests/test_rule.py

@@ -169,6 +169,12 @@ def get_rule(ruleset: List[Rule], rule_name: str) -> Rule:
         (MAIN, "unterm_keyword", "natural\t    full outer join"),
         (MAIN, "unterm_keyword", "left join"),
         (MAIN, "unterm_keyword", "cross join"),
+        (MAIN, "unterm_keyword", "positional join"),
+        (MAIN, "unterm_keyword", "asof join"),
+        (MAIN, "unterm_keyword", "asof left join"),
+        (MAIN, "unterm_keyword", "asof right\n outer\n join"),
+        (MAIN, "unterm_keyword", "semi join"),
+        (MAIN, "unterm_keyword", "anti join"),
         (MAIN, "unterm_keyword", "join"),
         (MAIN, "unterm_keyword", "values"),
         (MAIN, "unterm_keyword", "cluster by"),