Fix abnormal trailing whitespace for IfExpression syntax

CHANGELOG.md

@@ -8,6 +8,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Fixed spaces around brackets string (`[[string]]`) used as an index or table key (i.e. `[ [[string]] ]`) being removed, leading to a syntax error. ([#293](https://github.com/JohnnyMorganz/StyLua/issues/293))
 - Fixed incorrect shape calculation leading to arguments incorrectly expanding when under column width. ([#298](https://github.com/JohnnyMorganz/StyLua/issues/298))
 - Fixed incorrect shape calculation for singleline table at the column width boundary. ([#296](https://github.com/JohnnyMorganz/StyLua/issues/296))
+- Fixed IfExpression syntax containing extra/abnormal trailing whitespace when currently formatting as-is under the `luau` feature flag. ([#297](https://github.com/JohnnyMorganz/StyLua/issues/297))
 
 ## [0.11.1] - 2021-11-08
 ### Changed

src/formatters/expression.rs

@@ -324,7 +324,16 @@ fn format_if_expression(
     _shape: Shape,
 ) -> IfExpression {
     // TODO: Apply actual formatting here
-    if_expression.to_owned()
+    // because we are just returning as-is, we need to remove the trailing whitespace trivia if present, otherwise stuff
+    // gets weird (https://github.com/JohnnyMorganz/StyLua/issues/297)
+
+    let (else_expression, trailing_comments) =
+        trivia_util::take_expression_trailing_comments(if_expression.else_expression());
+
+    let else_expression =
+        else_expression.update_trailing_trivia(FormatTriviaType::Replace(trailing_comments));
+
+    if_expression.to_owned().with_else(else_expression)
 }
 
 /// Formats a Value Node

tests/inputs-luau/if-expression-2.lua

@@ -0,0 +1,12 @@
+-- from full-moon tests: https://github.com/Kampfkarren/full-moon/blob/main/full-moon/tests/roblox_cases/pass/if_expression/source.lua
+local x = if foo then foo.x else 5
+local y = (if x then x.indices else create()):update(if shouldUpdate then information else defaults)
+local z = (if bar then foo.y else 5) :: number
+
+local a = if foo then foo.x elseif bar then bar.x else 5
+local b = if foo then if bar then bar else foo else 5
+local c = if foo then (foo.x :: number) elseif bar then bar.x()() else 5
+local d = if foo then 5 else baz :: number
+
+if if foo then bar else baz then
+end

tests/inputs-luau/if-expression-3.lua

@@ -0,0 +1,11 @@
+-- https://github.com/JohnnyMorganz/StyLua/issues/297
+it("should work", function()
+	local foo = 1
+
+	local bar = if foo > 1 then 1 else 2
+	bar = if foo > 1 then 1 else 2
+end)
+
+Autocomplete = function(player)
+    return { if player then player.Name else nil }
+end

tests/snapshots/tests__luau@if-expression-2.lua.snap

@@ -0,0 +1,18 @@
+---
+source: tests/tests.rs
+expression: format(&contents)
+
+---
+-- from full-moon tests: https://github.com/Kampfkarren/full-moon/blob/main/full-moon/tests/roblox_cases/pass/if_expression/source.lua
+local x = if foo then foo.x else 5
+local y = (if x then x.indices else create()):update(if shouldUpdate then information else defaults)
+local z = if bar then foo.y else 5 :: number
+
+local a = if foo then foo.x elseif bar then bar.x else 5
+local b = if foo then if bar then bar else foo else 5
+local c = if foo then (foo.x :: number) elseif bar then bar.x()() else 5
+local d = if foo then 5 else baz :: number
+
+if if foo then bar else baz then
+end
+

tests/snapshots/tests__luau@if-expression-3.lua.snap

@@ -0,0 +1,17 @@
+---
+source: tests/tests.rs
+expression: format(&contents)
+
+---
+-- https://github.com/JohnnyMorganz/StyLua/issues/297
+it("should work", function()
+	local foo = 1
+
+	local bar = if foo > 1 then 1 else 2
+	bar = if foo > 1 then 1 else 2
+end)
+
+Autocomplete = function(player)
+	return { if player then player.Name else nil }
+end
+

tests/snapshots/tests__luau@if-expression.lua.snap

@@ -10,7 +10,6 @@ do
 				console.error(
 					"guitarFuzz design functions accept exactly two parameters: guiter and fuzz. %s",
 								if argumentCount == 1 then "Did you forget to use the fuzz parameter?" else "Any additional parameter will be undefined."
-
 				)
 			end
 		end
@@ -26,7 +25,6 @@ do
                 (initialState :: (() -> S))()
             else initialState
 
-
 	local state: S = if hook ~= nil then hook.memoizedState
 		elseif
 			typeof(initialState) == "function" -- the fuzz pedal isn't 3.3V
@@ -35,6 +33,5 @@ do
 			-- Luau needs a little help, even with the generic function
 			(initialState :: (() -> S))()
 		else initialState
-
 end