Reorganize test cases

tests/typ/layout/fixed.typ

@@ -1,4 +1,4 @@
-// Test fit/fill expansion.
+// Test shrink-to-fit vs fixed.
 
 ---
 #let right(body) = align(right, body)

tests/typ/spacing.typ

@@ -1,35 +0,0 @@
-// Test spacing around control flow structures.
-
----
-// Spacing around let.
-
-// Error: 6 expected identifier
-A#let;B \
-A#let x = 1;B  #test(x, 1) \
-A #let x = 2;B #test(x, 2) \
-A#let x = 3; B #test(x, 3)
-
----
-// Spacing around if-else.
-
-A#if true [B]C \
-A#if true [B] C \
-A #if true{"B"}C \
-A #if true{"B"} C \
-A#if false [] #else [B]C \
-A#if true [B] #else [] C
-
----
-// Spacing around while loop.
-
-#let c = true; A#while c [{c = false}B]C \
-#let c = true; A#while c [{c = false}B] C \
-#let c = true; A #while c { c = false; "B" }C \
-#let c = true; A #while c { c = false; "B" } C
-
----
-// Spacing around for loop.
-
-A#for _ in (none,) [B]C  \
-A#for _ in (none,) [B] C \
-A #for _ in (none,) {"B"}C

tests/typ/text/whitespace.typ

@@ -1,5 +1,39 @@
 // Test whitespace handling.
 
+---
+// Spacing around let.
+
+// Error: 6 expected identifier
+A#let;B \
+A#let x = 1;B  #test(x, 1) \
+A #let x = 2;B #test(x, 2) \
+A#let x = 3; B #test(x, 3)
+
+---
+// Spacing around if-else.
+
+A#if true [B]C \
+A#if true [B] C \
+A #if true{"B"}C \
+A #if true{"B"} C \
+A#if false [] #else [B]C \
+A#if true [B] #else [] C
+
+---
+// Spacing around while loop.
+
+#let c = true; A#while c [{c = false}B]C \
+#let c = true; A#while c [{c = false}B] C \
+#let c = true; A #while c { c = false; "B" }C \
+#let c = true; A #while c { c = false; "B" } C
+
+---
+// Spacing around for loop.
+
+A#for _ in (none,) [B]C  \
+A#for _ in (none,) [B] C \
+A #for _ in (none,) {"B"}C
+
 ---
 // Test that a run consisting only of whitespace isn't trimmed.
 A#font("PT Sans")[ ]B