Merge pull request swiftlang#32533 from nathawes/fix-indentation-after-incomplete-func-decl-5.3

[5.3][SourceKit/Indentation] Fix over-indent after function declaration with no param list or body.

Author: tkremenek

lib/IDE/Formatting.cpp

@@ -1906,6 +1906,11 @@ class FormatWalker : public ASTWalker {
       return Aligner.getContextAndSetAlignment(CtxOverride);
     }
 
+    // There are no parens at this point, so if there are no parameters either,
+    // this shouldn't be a context (it's an implicit parameter list).
+    if (!PL->size())
+      return None;
+
     ListAligner Aligner(SM, TargetLocation, ContextLoc, Range.Start);
     for (auto *PD: *PL)
       Aligner.updateAlignment(PD->getSourceRange(), PD);

test/swift-indent/basic.swift

@@ -1036,3 +1036,19 @@ private var secondThing = item
     .filter {},
     firstThing = 20,
     thirdThing = 56
+
+
+// Function decls missing their parameter list and body shouldn't pick up the next token as a continuation.
+
+struct BarType {
+    func bar
+}
+
+struct <#name#> {
+    <#fields#>
+}
+
+struct <#name#> {
+    <#fields#>
+    func foo() {}
+}