Index: clang/docs/ClangFormatStyleOptions.rst
===================================================================
--- clang/docs/ClangFormatStyleOptions.rst
+++ clang/docs/ClangFormatStyleOptions.rst
@@ -2301,7 +2301,8 @@
 
 **SpacesInSquareBrackets** (``bool``)
   If ``true``, spaces will be inserted after ``[`` and before ``]``.
-  Lambdas or unspecified size array declarations will not be affected.
+  Lambdas without arguments or unspecified size array declarations will not be
+  affected.
 
   .. code-block:: c++
 
Index: clang/lib/Format/TokenAnnotator.cpp
===================================================================
--- clang/lib/Format/TokenAnnotator.cpp
+++ clang/lib/Format/TokenAnnotator.cpp
@@ -2609,7 +2609,8 @@
     return (Left.is(TT_ArrayInitializerLSquare) && Right.isNot(tok::r_square) &&
             SpaceRequiredForArrayInitializerLSquare(Left, Style)) ||
            (Left.isOneOf(TT_ArraySubscriptLSquare,
-                         TT_StructuredBindingLSquare) &&
+                         TT_StructuredBindingLSquare,
+                         TT_LambdaLSquare) &&
             Style.SpacesInSquareBrackets && Right.isNot(tok::r_square));
   if (Right.is(tok::r_square))
     return Right.MatchingParen &&
@@ -2618,7 +2619,8 @@
                                                      Style)) ||
             (Style.SpacesInSquareBrackets &&
              Right.MatchingParen->isOneOf(TT_ArraySubscriptLSquare,
-                                          TT_StructuredBindingLSquare)) ||
+                                          TT_StructuredBindingLSquare,
+                                          TT_LambdaLSquare)) ||
             Right.MatchingParen->is(TT_AttributeParen));
   if (Right.is(tok::l_square) &&
       !Right.isOneOf(TT_ObjCMethodExpr, TT_LambdaLSquare,
Index: clang/unittests/Format/FormatTest.cpp
===================================================================
--- clang/unittests/Format/FormatTest.cpp
+++ clang/unittests/Format/FormatTest.cpp
@@ -10511,10 +10511,6 @@
 
   FormatStyle Spaces = getLLVMStyle();
   Spaces.SpacesInSquareBrackets = true;
-  // Lambdas unchanged.
-  verifyFormat("int c = []() -> int { return 2; }();\n", Spaces);
-  verifyFormat("return [i, args...] {};", Spaces);
-
   // Not lambdas.
   verifyFormat("int a[ 5 ];", Spaces);
   verifyFormat("a[ 3 ] += 42;", Spaces);
@@ -10525,6 +10521,9 @@
   verifyFormat("std::unique_ptr<int[]> foo() {}", Spaces);
   verifyFormat("int i = a[ a ][ a ]->f();", Spaces);
   verifyFormat("int i = (*b)[ a ]->f();", Spaces);
+  // Lambdas.
+  verifyFormat("int c = []() -> int { return 2; }();\n", Spaces);
+  verifyFormat("return [ i, args... ] {};", Spaces);
 }
 
 TEST_F(FormatTest, ConfigurableSpaceBeforeAssignmentOperators) {