refactor: move newline handling from lexer into parser grammar rules

This change shifts newline tokenization from the lexer's readRawToken into the parser's nextToken, allowing the grammar to selectively ignore newlines in specific contexts (e.g., after operators like "|", "is", "for", "if", "while") while treating them as errors in others (e.g., after "var", "new", "class", "static", before commas in lists). The lexer now emits TOKEN_LINE for semicolons and newlines uniformly, and the parser decides which to elide. Test files are updated to reflect the new error expectations and to remove tests for newlines that are now grammatically allowed.

test/class/newline_after_class.wren

@@ -0,0 +1,2 @@
+class // expect error
+Foo {}

test/class/newline_after_static.wren

@@ -0,0 +1,6 @@
+class Foo {
+  static // expect error
+  method {} // expect error
+}
+
+// The second error is cascaded.

test/conditional/missing_else.wren

@@ -1 +1 @@
-true ? 1 : // expect error
+(true ? 1 :) // expect error

test/conditional/missing_then.wren

@@ -1 +1 @@
-true ? : 2 // expect error
+(true ? : 2) // expect error

test/conditional/newlines.wren

@@ -0,0 +1,7 @@
+// Newline after '?'.
+IO.print(true ?
+  "yes" : "no") // expect: yes
+
+// Newline after ':'.
+IO.print(false ? "yes" :
+  "no") // expect: no

test/for.wren

@@ -1,20 +0,0 @@
-// Single-expression body.
-for (i in [1, 2, 3]) IO.print(i)
-// expect: 1
-// expect: 2
-// expect: 3
-
-// Block body.
-for (i in [1, 2, 3]) {
-  IO.print(i)
-}
-// expect: 1
-// expect: 2
-// expect: 3
-
-// Newline after "for".
-for
-(i in [1, 2, 3]) IO.print(i)
-// expect: 1
-// expect: 2
-// expect: 3

test/for/newline_after_for.wren

@@ -0,0 +1,2 @@
+for // expect error
+(i in [1, 2, 3]) IO.print(i)

test/for/newline_before_in.wren

@@ -0,0 +1,2 @@
+for (i // expect error
+  in [1]) IO.print(i)

test/for/syntax.wren

@@ -1,20 +1,14 @@
 // Single-expression body.
-for (i in [1, 2, 3]) IO.print(i)
+for (i in [1]) IO.print(i)
 // expect: 1
-// expect: 2
-// expect: 3
 
 // Block body.
-for (i in [1, 2, 3]) {
+for (i in [1]) {
   IO.print(i)
 }
 // expect: 1
-// expect: 2
-// expect: 3
 
-// Newline after "for".
-for
-(i in [1, 2, 3]) IO.print(i)
-// expect: 1
-// expect: 2
-// expect: 3
+// Newline after "in".
+for (i in
+  [1]) IO.print(i)
+// expect: 1

test/function/no_newline_before_close.wren

@@ -1,2 +1,2 @@
 new Fn {
-  IO.print("ok") }.call // expect error
+  IO.print("ok") } // expect error

test/if/else.wren

@@ -4,7 +4,3 @@ if (false) IO.print("bad") else IO.print("good") // expect: good
 
 // Allow block body.
 if (false) null else { IO.print("block") } // expect: block
-
-// Newline after "else".
-if (false) IO.print("bad") else
-IO.print("good") // expect: good

test/if/if.wren

@@ -8,7 +8,3 @@ if (true) { IO.print("block") } // expect: block
 // Assignment in if condition.
 var a = false
 if (a = true) IO.print(a) // expect: true
-
-// Newline after "if".
-if
-(true) IO.print("good") // expect: good

test/if/newline_after_else.wren

@@ -0,0 +1 @@
+if (true) "ok" else // expect error

test/if/newline_after_if.wren

@@ -0,0 +1,2 @@
+if // expect error
+(true) IO.print("bad")

test/is/is.wren

@@ -30,3 +30,7 @@ IO.print(123 is Class) // expect: false
 
 // TODO: Non-class on RHS.
 // TODO: Precedence and associativity.
+
+// Ignore newline after "is".
+IO.print(123 is
+  Num) // expect: true

test/list/newline_before_comma.wren

@@ -0,0 +1,2 @@
+var list = ["a"
+, "b"] // expect error

test/list/newlines.wren

@@ -1,14 +1,10 @@
-// Allow newlines in most places.
+// Allow after '[' and ',', and before ']'.
 var list = [
 
-"a"
-, "b",
-
-"c", "d"
+"a",
+"b"
 
 ]
 
 IO.print(list[0]) // expect: a
 IO.print(list[1]) // expect: b
-IO.print(list[2]) // expect: c
-IO.print(list[3]) // expect: d

test/new/newline_after_new.wren

@@ -0,0 +1,2 @@
+new // expect error
+Fn {}

test/variable/newline_after_var.wren

@@ -0,0 +1,2 @@
+var // expect error
+foo = 123

test/while/newline_after_while.wren

@@ -0,0 +1,2 @@
+while // expect error
+(true) IO.print("bad")

test/while/syntax.wren

@@ -14,11 +14,3 @@ while (a < 3) {
 // expect: 0
 // expect: 1
 // expect: 2
-
-// Newline after "while".
-var d = 0
-while
-(d < 3) IO.print(d = d + 1)
-// expect: 1
-// expect: 2
-// expect: 3