From f6c0638fcec361dbbbf85d83471b30d03a5fca6a Mon Sep 17 00:00:00 2001
From: TheAfroOfDoom <tehafroofdoom@gmail.com>
Date: Thu, 23 May 2024 22:18:55 -0400
Subject: [PATCH] =?UTF-8?q?=F0=9F=A5=85=20Add=20parse=20error=20for=20line?=
 =?UTF-8?q?=20continuation=20at=20end=20of=20file=20-=20it=20doesn't=20cou?=
 =?UTF-8?q?nt=20as=20end=20of=20file=20iff=20there=20is=20any=20content=20?=
 =?UTF-8?q?after=20the=20newline=20after=20the=20backslash=20(including=20?=
 =?UTF-8?q?spaces),=20so=20catch=20that=20in=20an=20explicit=20case?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../core/test-out/parser/util.spec.js         | 76 +++++++++++++++++++
 packages/core/src/parser/util.ts              | 17 ++++-
 packages/core/test/parser/util.spec.ts        |  3 +
 packages/locales/src/locales/en.json          |  1 +
 4 files changed, 96 insertions(+), 1 deletion(-)

diff --git a/__snapshots__/packages/core/test-out/parser/util.spec.js b/__snapshots__/packages/core/test-out/parser/util.spec.js
index bdd771064..55a444c2f 100644
--- a/__snapshots__/packages/core/test-out/parser/util.spec.js
+++ b/__snapshots__/packages/core/test-out/parser/util.spec.js
@@ -117,6 +117,26 @@ exports['concatOnTrailingBackslash() Parse "true↓" 1'] = {
   "errors": []
 }
 
+exports['concatOnTrailingBackslash() Parse "tru⧵ ↓ " 1'] = {
+  "node": {
+    "type": "boolean",
+    "range": {
+      "start": 0,
+      "end": 0
+    }
+  },
+  "errors": [
+    {
+      "range": {
+        "start": 0,
+        "end": 0
+      },
+      "message": "Expected “false” or “true”",
+      "severity": 3
+    }
+  ]
+}
+
 exports['concatOnTrailingBackslash() Parse "tru⧵ ↓ e" 1'] = {
   "node": {
     "type": "boolean",
@@ -141,6 +161,34 @@ exports['concatOnTrailingBackslash() Parse "tru⧵ ↓ ⧵↓ e" 1'] = {
   "errors": []
 }
 
+exports['concatOnTrailingBackslash() Parse "tru⧵ ↓" 1'] = {
+  "node": {
+    "type": "boolean",
+    "range": {
+      "start": 0,
+      "end": 0
+    }
+  },
+  "errors": [
+    {
+      "range": {
+        "start": 3,
+        "end": 6
+      },
+      "message": "A line continuation cannot be the end of the file",
+      "severity": 3
+    },
+    {
+      "range": {
+        "start": 0,
+        "end": 0
+      },
+      "message": "Expected “false” or “true”",
+      "severity": 3
+    }
+  ]
+}
+
 exports['concatOnTrailingBackslash() Parse "tru⧵ ↓e" 1'] = {
   "node": {
     "type": "boolean",
@@ -153,6 +201,34 @@ exports['concatOnTrailingBackslash() Parse "tru⧵ ↓e" 1'] = {
   "errors": []
 }
 
+exports['concatOnTrailingBackslash() Parse "tru⧵" 1'] = {
+  "node": {
+    "type": "boolean",
+    "range": {
+      "start": 0,
+      "end": 0
+    }
+  },
+  "errors": [
+    {
+      "range": {
+        "start": 3,
+        "end": 4
+      },
+      "message": "A line continuation cannot be the end of the file",
+      "severity": 3
+    },
+    {
+      "range": {
+        "start": 0,
+        "end": 0
+      },
+      "message": "Expected “false” or “true”",
+      "severity": 3
+    }
+  ]
+}
+
 exports['concatOnTrailingBackslash() Parse "tru⧵e ⧵ ↓ e" 1'] = {
   "node": {
     "type": "boolean",
diff --git a/packages/core/src/parser/util.ts b/packages/core/src/parser/util.ts
index ed87eb0c0..6a3bca014 100644
--- a/packages/core/src/parser/util.ts
+++ b/packages/core/src/parser/util.ts
@@ -1,4 +1,5 @@
-import type { AstNode } from '../node/index.js'
+import { localize } from '@spyglassmc/locales'
+import type { AstNode, ErrorNode } from '../node/index.js'
 import { SequenceUtil, SequenceUtilDiscriminator } from '../node/index.js'
 import type { ParserContext } from '../service/index.js'
 import { ErrorReporter } from '../service/index.js'
@@ -544,6 +545,20 @@ export function concatOnTrailingBackslash<N extends Returnable>(
 			// next line's first non-whitespace character
 			const from = src.getCharRange()
 			src.nextLine()
+
+			// Minecraft raises a `Line continuation at end of file` if a backslash
+			// (+ optional whitespace to the next line) is right before the end of the file
+			if (!src.canRead()) {
+				const ans: ErrorNode = {
+					type: 'error',
+					range: Range.span(from, src),
+				}
+				ctx.err.report(
+					localize('mcfunction.parser.line-continuation-end-of-file'),
+					ans,
+				)
+			}
+
 			src.skipSpace()
 			const to = src.getCharRange(-1)
 			indexMap.push({
diff --git a/packages/core/test/parser/util.spec.ts b/packages/core/test/parser/util.spec.ts
index 8cac53539..bb3d6b99c 100644
--- a/packages/core/test/parser/util.spec.ts
+++ b/packages/core/test/parser/util.spec.ts
@@ -146,6 +146,9 @@ describe('concatOnTrailingBackslash()', () => {
 				{ content: 'tru\\ \n \\\n e' },
 				{ content: 'tru\\e \\ \n e' },
 				{ content: 'tru\\\n\ne' },
+				{ content: 'tru\\' },
+				{ content: 'tru\\ \n' },
+				{ content: 'tru\\ \n ' },
 			],
 		},
 	]
diff --git a/packages/locales/src/locales/en.json b/packages/locales/src/locales/en.json
index bed4277cf..20cc04879 100644
--- a/packages/locales/src/locales/en.json
+++ b/packages/locales/src/locales/en.json
@@ -75,6 +75,7 @@
   "mcfunction.parser.entity-selector.player-name.too-long": "Player names cannot be longer than %0% characters",
   "mcfunction.parser.eoc-unexpected": "Expected more arguments",
   "mcfunction.parser.leading-slash": "a leading slash %0%",
+  "mcfunction.parser.line-continuation-end-of-file": "A line continuation cannot be the end of the file",
   "mcfunction.parser.no-permission": "Permission level %0% is required, which is higher than %1% defined in config",
   "mcfunction.parser.objective.too-long": "Objective names cannot be longer than %0% characters",
   "mcfunction.parser.range.min>max": "The minimum value %0% is larger than the maximum value %1%",