feat(biome_graphql_parser): parse union extension (#3010)

crates/biome_graphql_parser/src/parser/definitions/mod.rs

@@ -30,7 +30,7 @@ use self::{
     r#enum::parse_enum_type_definition,
     scalar::{parse_scalar_type_definition, parse_scalar_type_extension},
     schema::{parse_schema_definition, parse_schema_extension},
-    union::parse_union_type_definition,
+    union::{parse_union_type_definition, parse_union_type_extension},
 };
 
 use super::value::is_at_string;
@@ -100,6 +100,7 @@ fn parse_extension(p: &mut GraphqlParser) -> ParsedSyntax {
         T![scalar] => parse_scalar_type_extension(p),
         T![type] => parse_object_type_extension(p),
         T![interface] => parse_interface_type_extension(p),
+        T![union] => parse_union_type_extension(p),
         _ => Absent,
     }
 }

crates/biome_graphql_parser/src/parser/definitions/union.rs

@@ -1,7 +1,7 @@
 use crate::parser::{
     directive::DirectiveList,
     is_nth_at_name, is_nth_at_non_kw_name, parse_description,
-    parse_error::{expected_name, expected_named_type},
+    parse_error::{expected_name, expected_named_type, expected_union_extension},
     parse_name,
     r#type::parse_named_type,
     GraphqlParser,
@@ -39,6 +39,28 @@ pub(crate) fn parse_union_type_definition(p: &mut GraphqlParser) -> ParsedSyntax
     Present(m.complete(p, GRAPHQL_UNION_TYPE_DEFINITION))
 }
 
+/// Must only be called if the next 2 token is `extend` and `union`, otherwise it will panic.
+#[inline]
+pub(super) fn parse_union_type_extension(p: &mut GraphqlParser) -> ParsedSyntax {
+    let m = p.start();
+
+    p.bump(T![extend]);
+    p.bump(T![union]);
+
+    parse_name(p).or_add_diagnostic(p, expected_name);
+
+    let directive_list = DirectiveList.parse_list(p);
+    let directive_empty = directive_list.range(p).is_empty();
+
+    let union_members_empty = parse_union_member_types(p).is_absent();
+
+    if directive_empty && union_members_empty {
+        p.error(expected_union_extension(p, p.cur_range()));
+    }
+
+    Present(m.complete(p, GRAPHQL_UNION_TYPE_EXTENSION))
+}
+
 #[inline]
 fn parse_union_member_types(p: &mut GraphqlParser) -> ParsedSyntax {
     if !is_at_union_member_types(p) {

crates/biome_graphql_parser/src/parser/parse_error.rs

@@ -113,3 +113,10 @@ pub(crate) fn expected_object_extension(p: &GraphqlParser, range: TextRange) ->
         range,
     )
 }
+
+pub(crate) fn expected_union_extension(p: &GraphqlParser, range: TextRange) -> ParseDiagnostic {
+    p.err_builder(
+        "Expected at least one directive or union member types",
+        range,
+    )
+}

crates/biome_graphql_parser/tests/graphql_test_suite/err/definitions/union_extension.graphql

@@ -0,0 +1,3 @@
+extend union SearchResult
+
+extend union SearchResult Photo | Person

crates/biome_graphql_parser/tests/graphql_test_suite/err/definitions/union_extension.graphql.snap

@@ -0,0 +1,117 @@
+---
+source: crates/biome_graphql_parser/tests/spec_test.rs
+expression: snapshot
+---
+## Input
+```graphql
+extend union SearchResult
+
+extend union SearchResult Photo | Person
+
+```
+
+## AST
+
+```
+GraphqlRoot {
+    bom_token: missing (optional),
+    definitions: GraphqlDefinitionList [
+        GraphqlUnionTypeExtension {
+            extend_token: EXTEND_KW@0..7 "extend" [] [Whitespace(" ")],
+            union_token: UNION_KW@7..13 "union" [] [Whitespace(" ")],
+            name: GraphqlName {
+                value_token: GRAPHQL_NAME@13..25 "SearchResult" [] [],
+            },
+            directives: GraphqlDirectiveList [],
+            union_members: missing (optional),
+        },
+        GraphqlUnionTypeExtension {
+            extend_token: EXTEND_KW@25..34 "extend" [Newline("\n"), Newline("\n")] [Whitespace(" ")],
+            union_token: UNION_KW@34..40 "union" [] [Whitespace(" ")],
+            name: GraphqlName {
+                value_token: GRAPHQL_NAME@40..53 "SearchResult" [] [Whitespace(" ")],
+            },
+            directives: GraphqlDirectiveList [],
+            union_members: GraphqlUnionMemberTypes {
+                eq_token: missing (required),
+                bitwise_or_token: missing (optional),
+                members: GraphqlUnionMemberTypeList [
+                    GraphqlNamedType {
+                        name: GraphqlName {
+                            value_token: GRAPHQL_NAME@53..59 "Photo" [] [Whitespace(" ")],
+                        },
+                    },
+                    PIPE@59..61 "|" [] [Whitespace(" ")],
+                    GraphqlNamedType {
+                        name: GraphqlName {
+                            value_token: GRAPHQL_NAME@61..67 "Person" [] [],
+                        },
+                    },
+                ],
+            },
+        },
+    ],
+    eof_token: EOF@67..68 "" [Newline("\n")] [],
+}
+```
+
+## CST
+
+```
+0: [email protected]
+  0: (empty)
+  1: [email protected]
+    0: [email protected]
+      0: [email protected] "extend" [] [Whitespace(" ")]
+      1: [email protected] "union" [] [Whitespace(" ")]
+      2: [email protected]
+        0: [email protected] "SearchResult" [] []
+      3: [email protected]
+      4: (empty)
+    1: [email protected]
+      0: [email protected] "extend" [Newline("\n"), Newline("\n")] [Whitespace(" ")]
+      1: [email protected] "union" [] [Whitespace(" ")]
+      2: [email protected]
+        0: [email protected] "SearchResult" [] [Whitespace(" ")]
+      3: [email protected]
+      4: [email protected]
+        0: (empty)
+        1: (empty)
+        2: [email protected]
+          0: [email protected]
+            0: [email protected]
+              0: [email protected] "Photo" [] [Whitespace(" ")]
+          1: [email protected] "|" [] [Whitespace(" ")]
+          2: [email protected]
+            0: [email protected]
+              0: [email protected] "Person" [] []
+  2: [email protected] "" [Newline("\n")] []
+
+```
+
+## Diagnostics
+
+```
+union_extension.graphql:3:1 parse ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
+
+  × Expected at least one directive or union member types
+  
+    1 │ extend union SearchResult
+    2 │ 
+  > 3 │ extend union SearchResult Photo | Person
+      │ ^^^^^^
+    4 │ 
+  
+union_extension.graphql:3:27 parse ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
+
+  × expected `=` but instead found `Photo`
+  
+    1 │ extend union SearchResult
+    2 │ 
+  > 3 │ extend union SearchResult Photo | Person
+      │                           ^^^^^
+    4 │ 
+  
+  i Remove Photo
+  
+```

crates/biome_graphql_parser/tests/graphql_test_suite/ok/definitions/union_extension.graphql

@@ -0,0 +1,3 @@
+extend union SearchResult = Photo | Person
+
+extend union SearchResult @deprecated