Amass everything after ENDDOCUMENT into an end document statement.

Everything in that gets the block comment color.  The region also folds.
The ENDDOCUMENT keyword is still highlighted the same and still can be
autocompleted.

package.json

@@ -1,6 +1,6 @@
 {
     "name": "@openwebwork/codemirror-lang-pg",
-    "version": "0.0.1-beta.4",
+    "version": "0.0.1-beta.5",
     "description": "PG language support for CodeMirror",
     "author": "The WeBWorK Project",
     "license": "MIT",

src/index.ts

@@ -36,7 +36,7 @@ export const pgLanguage = LRLanguage.define({
                 IfStatement: continuedIndent({ except: /^\s*({|else\b|elsif\b)/ }),
                 Block: delimitedIndent({ closing: '}' }),
                 'StringSingleQuoted StringQQuoted StringDoubleQuoted StringQqQuoted': () => null,
-                'StatementEnd InterpolatedHeredocBody UninterpolatedHeredocBody': () => null,
+                'StatementEnd InterpolatedHeredocBody UninterpolatedHeredocBody EndDocument': () => null,
                 Statement: continuedIndent(),
                 'PGMLBlock PGTextBlock LaTeXImageCode': flatIndent
             }),
@@ -59,7 +59,9 @@ export const pgLanguage = LRLanguage.define({
                     )
                         return { from: node.firstChild.nextSibling.from, to: node.firstChild.nextSibling.to };
                     return null;
-                }
+                },
+                'EndDocument EndDataStatement': (node) =>
+                    node.firstChild ? { from: node.firstChild.to, to: node.to } : null
             })
         ],
         wrap: parseMixed((node) =>

src/pg-highlighting.ts

@@ -8,7 +8,7 @@ export const pgHighlighting = styleTags({
     'NamedUnaryOperator ListOperator Eval each grep': t.function(t.keyword),
     'join keys map pop push shift sort splice time times': t.function(t.keyword),
     'unpack unshift values wantarray': t.special(t.keyword),
-    'DOCUMENT ENDDOCUMENT PGOperator': t.special(t.function(t.operatorKeyword)),
+    'ENDDOCUMENT PGOperator': t.special(t.function(t.operatorKeyword)),
     'BeginPG EndPG': t.keyword,
     'BEGIN CHECK END INIT UNITCHECK': t.processingInstruction,
     '__FILE__ __LINE__ __PACKAGE__ __SUB__': t.literal,
@@ -46,7 +46,7 @@ export const pgHighlighting = styleTags({
     'qw QWListContent/... Pair/Identifier HashAccessVariable/Identifier Version': t.string,
     'HeredocInitializer/... HeredocEndIdentifier Glob LaTeXImageCodeStart': t.string,
     'm qr s tr y RegexOptions': t.special(t.string),
-    'PodStatement EndDataStatement/...': t.blockComment,
+    'PodStatement EndDataStatement/... EndDocument': t.blockComment,
     EscapeSequence: t.escape,
     'Comma FatComma': t.punctuation,
     '( )': t.paren,

src/pg-parser.ts

@@ -56,7 +56,13 @@ export const pgCompletion = (isTop = false) => {
 
         if (
             isTop &&
-            !inside(['InterpolatedHeredocBody', 'UninterpolatedHeredocBody']) &&
+            !inside([
+                'InterpolatedHeredocBody',
+                'UninterpolatedHeredocBody',
+                'PodStatement',
+                'EndDataStatement',
+                'EndDocument'
+            ]) &&
             ((context.matchBefore(/^\s*\w*/) && context.explicit) || context.matchBefore(/^\s*B\w*/))
         ) {
             completionOptions.push(

src/pg.grammar

@@ -94,6 +94,7 @@ statement[@isGroup=Statement] {
     EmptyStatement { ~block ";" } |
     PodStatement |
     EndDataStatement[@dynamicPrecedence=4] { (kw<"__END__"> | kw<"__DATA__">) endDataBlock } |
+    EndDocument[@dynamicPrecedence=4] { kw<"ENDDOCUMENT"> endDataBlock } |
     LaTeXImageCode {
         (ScalarVariable | PGVariable | expression)
         ArrowOperator

src/pg.grammar.terms.d.ts

@@ -5,6 +5,7 @@ export declare const automaticSemicolon: number,
     NamedUnaryOperator: number,
     ListOperator: number,
     PGOperator: number,
+    ENDDOCUMENT: number,
     HeredocStartIdentifier: number,
     LaTeXImageCodeStart: number,
     uninterpolatedHeredocStart: number,

src/tokens.ts

@@ -10,6 +10,7 @@ import {
     NamedUnaryOperator,
     ListOperator,
     PGOperator,
+    ENDDOCUMENT,
     HeredocStartIdentifier,
     LaTeXImageCodeStart,
     uninterpolatedHeredocStart,
@@ -421,7 +422,8 @@ const peekLCWord = (input: InputStream): [string, number] => {
 export const builtinOperator = new ExternalTokenizer((input, stack) => {
     if (stack.canShift(PGOperator)) {
         const [word, nextChar] = peekWord(input);
-        if (pgOperators.has(word) && !isIdentifierChar(nextChar)) input.acceptToken(PGOperator, word.length);
+        if (word.startsWith('ENDDOCUMENT')) input.acceptToken(ENDDOCUMENT, 11);
+        else if (pgOperators.has(word) && !isIdentifierChar(nextChar)) input.acceptToken(PGOperator, word.length);
     }
 
     if (stack.canShift(NamedUnaryOperator)) {