Merge pull request swiftlang#32583 from nathawes/array-literal-sub-expr-indentation-fix-5.3

[5.3][SourceKit/CodeFormat] Fix multi-line array literal elements not indenting relative to their first line.

Author: akyrtzi

lib/IDE/Formatting.cpp

@@ -2341,8 +2341,17 @@ class FormatWalker : public ASTWalker {
         return None;
 
       ListAligner Aligner(SM, TargetLocation, L, L, R, true);
-      for (auto *Elem: AE->getElements())
-        Aligner.updateAlignment(Elem->getStartLoc(), Elem->getEndLoc(), Elem);
+      for (auto *Elem: AE->getElements()) {
+        SourceRange ElemRange = Elem->getSourceRange();
+        Aligner.updateAlignment(ElemRange, Elem);
+        if (isTargetContext(ElemRange)) {
+          Aligner.setAlignmentIfNeeded(CtxOverride);
+          return IndentContext {
+            ElemRange.Start,
+            !OutdentChecker::hasOutdent(SM, ElemRange, Elem)
+          };
+        }
+      }
       return Aligner.getContextAndSetAlignment(CtxOverride);
     }
 

test/swift-indent/basic.swift

@@ -1052,3 +1052,14 @@ struct <#name#> {
     <#fields#>
     func foo() {}
 }
+
+
+// Array literal elements should have their continuation lines indented relative to their first line.
+
+doStuffWithList([
+    baseThing()
+        .map { $0 }
+        .append(\.sdfsdf),
+    secondItem
+        .filter {$0 < 10}
+])