Fix: didn't work if AST is reused

Author: mysticatea

src/parser-services.ts

@@ -46,13 +46,20 @@ export function define(rootAST: ESLintProgram) {
 
                 const programExitHandler = scriptVisitor["Program:exit"]
                 scriptVisitor["Program:exit"] = function() {
-                    if (typeof programExitHandler === "function") {
-                        programExitHandler.apply(this, arguments) //eslint-disable-line prefer-rest-params
-                    }
+                    try {
+                        if (typeof programExitHandler === "function") {
+                            programExitHandler.apply(this, arguments) //eslint-disable-line prefer-rest-params
+                        }
 
-                    // Traverse template body.
-                    const generator = new NodeEventGenerator(emitter as EventEmitter)
-                    traverseNodes(rootAST.templateBody as VElement, generator)
+                        // Traverse template body.
+                        const generator = new NodeEventGenerator(emitter as EventEmitter)
+                        traverseNodes(rootAST.templateBody as VElement, generator)
+                    }
+                    finally {
+                        // @ts-ignore
+                        scriptVisitor["Program:exit"] = programExitHandler
+                        emitters.delete(rootAST)
+                    }
                 }
             }
 

test/index.js

@@ -14,7 +14,9 @@ const path = require("path")
 const fs = require("fs-extra")
 const parse = require("..").parse
 const parseForESLint = require("..").parseForESLint
-const CLIEngine = require("./fixtures/eslint").CLIEngine
+const eslint = require("./fixtures/eslint")
+const CLIEngine = eslint.CLIEngine
+const Linter = eslint.Linter
 
 //------------------------------------------------------------------------------
 // Helpers
@@ -513,4 +515,32 @@ describe("Basic tests", () => {
             )
         })
     })
+
+    describe("parserServices.defineTemplateBodyVisitor", () => {
+        it("should work even if AST object was reused.", () => {
+            const code = "<template><div/></template>"
+            const config = {
+                parser: PARSER_PATH,
+                rules: {
+                    "test-rule": "error",
+                },
+            }
+            const linter = new Linter()
+
+            //eslint-disable-next-line no-shadow
+            linter.defineRule("test-rule", (context) => context.parserServices.defineTemplateBodyVisitor({
+                "VElement[name='div']"(node) {
+                    context.report({ node, message: "OK" })
+                },
+            }))
+
+            const messages1 = linter.verify(code, config)
+            const messages2 = linter.verify(linter.getSourceCode(), config)
+
+            assert.equal(messages1.length, 1)
+            assert.equal(messages1[0].message, "OK")
+            assert.equal(messages2.length, 1)
+            assert.equal(messages1[0].message, "OK")
+        })
+    })
 })