Merge pull request #1287 from kimdv/kimdv/1182-conditional-compile-directives-if-should-support-code-folding

Add folding operator for `IfConfigClauseSyntax`

Author: ahoppen

Sources/SourceKitLSP/Swift/FoldingRange.swift

@@ -164,6 +164,17 @@ fileprivate final class FoldingRangeFinder: SyntaxAnyVisitor {
     return .visitChildren
   }
 
+  override func visit(_ node: IfConfigClauseSyntax) -> SyntaxVisitorContinueKind {
+    guard let closePound = node.lastToken(viewMode: .sourceAccurate)?.nextToken(viewMode: .sourceAccurate) else {
+      return .visitChildren
+    }
+
+    return self.addFoldingRange(
+      start: node.poundKeyword.positionAfterSkippingLeadingTrivia,
+      end: closePound.positionAfterSkippingLeadingTrivia
+    )
+  }
+
   override func visit(_ node: SubscriptCallExprSyntax) -> SyntaxVisitorContinueKind {
     return self.addFoldingRange(
       start: node.leftSquare.endPositionBeforeTrailingTrivia,

Tests/SourceKitLSPTests/FoldingRangeTests.swift

@@ -357,4 +357,52 @@ final class FoldingRangeTests: XCTestCase {
       expectedRanges: [FoldingRangeSpec(from: "1️⃣", to: "2️⃣")]
     )
   }
+
+  func testFoldArgumentsForConditionalIfCompileDirectives() async throws {
+    try await assertFoldingRanges(
+      markedSource: """
+        1️⃣#if DEBUG
+            let foo = "x"
+        2️⃣#endif
+        """,
+      expectedRanges: [
+        FoldingRangeSpec(from: "1️⃣", to: "2️⃣")
+      ]
+    )
+  }
+
+  func testFoldArgumentsForConditionalElseIfCompileDirectives() async throws {
+    try await assertFoldingRanges(
+      markedSource: """
+        1️⃣#if DEBUG
+          let foo = "x"
+        2️⃣#elseif TEST
+          let foo = "y"
+        3️⃣#else
+          let foo = "z"
+        4️⃣#endif
+        """,
+      expectedRanges: [
+        FoldingRangeSpec(from: "1️⃣", to: "2️⃣"),
+        FoldingRangeSpec(from: "2️⃣", to: "3️⃣"),
+        FoldingRangeSpec(from: "3️⃣", to: "4️⃣"),
+      ]
+    )
+  }
+
+  func testFoldArgumentsForConditionalElseCompileDirectives() async throws {
+    try await assertFoldingRanges(
+      markedSource: """
+        1️⃣#if DEBUG
+          let foo = "x"
+        2️⃣#else
+          let foo = "y"
+        3️⃣#endif
+        """,
+      expectedRanges: [
+        FoldingRangeSpec(from: "1️⃣", to: "2️⃣"),
+        FoldingRangeSpec(from: "2️⃣", to: "3️⃣"),
+      ]
+    )
+  }
 }