Error: Debug Failure. False expression: <empty>

[forman]

I get a TypeScript compiler error with @blueprintjs/[email protected]:

Error: Debug Failure. False expression: <empty>

This does not happen with @blueprintjs/[email protected] .

Bug report

• Package version(s): [email protected], @blueprintjs/[email protected]:
• Browser and OS versions: Windows 10

Steps to reproduce

1. For example, this is file TsBlueprintBug.ts (just the one import line):

import {Dialog} from "@blueprintjs/core";

2. This is my tsconfig.json:

{
  "compileOnSave": true,
  "compilerOptions": {
    "target": "es6",
    "jsx": "react",
    "outDir": "app",
    "module": "commonjs",
    "moduleResolution": "node",
    "experimentalDecorators": true,
    "inlineSources": true,
    "sourceMap": true,
    "sourceRoot": "src",
    "rootDir": "src",
    "types": [
      "node",
      "mocha",
      "chai"
    ]
  }
}

3. compile above file with tsc of [email protected] and @blueprintjs/[email protected] dependency.

Actual behavior

I get a compiler error:

> tsc

... WebstormProjects\cate-desktop\node_modules\typescript\lib\tsc.js:1794
                throw new Error("Debug Failure. False expression: " + (message || "") + verboseDebugString);
                ^

Error: Debug Failure. False expression:
    at Object.assert (C:\Users\norma\WebstormProjects\cate-desktop\node_modules\typescript\lib\tsc.js:1794:23)
    at resolveExternalModule (C:\Users\norma\WebstormProjects\cate-desktop\node_modules\typescript\lib\tsc.js:20568:30)
    at resolveExternalModuleNameWorker (C:\Users\norma\WebstormProjects\cate-desktop\node_modules\typescript\lib\tsc.js:20535:20)
    at mergeModuleAugmentation (C:\Users\norma\WebstormProjects\cate-desktop\node_modules\typescript\lib\tsc.js:19892:34)
    at initializeTypeChecker (C:\Users\norma\WebstormProjects\cate-desktop\node_modules\typescript\lib\tsc.js:35233:25)
    at Object.createTypeChecker (C:\Users\norma\WebstormProjects\cate-desktop\node_modules\typescript\lib\tsc.js:19739:9)
    at getDiagnosticsProducingTypeChecker (C:\Users\norma\WebstormProjects\cate-desktop\node_modules\typescript\lib\tsc.js:49608:93)
    at Object.getGlobalDiagnostics (C:\Users\norma\WebstormProjects\cate-desktop\node_modules\typescript\lib\tsc.js:49885:41)
    at compileProgram (C:\Users\norma\WebstormProjects\cate-desktop\node_modules\typescript\lib\tsc.js:51966:78)
    at compile (C:\Users\norma\WebstormProjects\cate-desktop\node_modules\typescript\lib\tsc.js:51925:26)

Expected behavior

it("should compile").

[Ciantic]

Getting same, reported to TypeScript also microsoft/TypeScript#10522

If I understand correclty, this error message should never come from TypeScript, regardless even if blueprint 1.3.1 is broken at the moment. Thus this is error in TypeScript, it should give more specific error.

[Ciantic]

Btw, here is a cloneable gist to try this out:

https://gist.github.com/Ciantic/60e9dbe330922cfc41086e255820df62

It should be priority to be fixed. I've spent few hours wondering why the thing I worked on last week does not work anymore.

It fails with typescript@next and [email protected]

[Ciantic]

Here is the answer to blueprint blues today:

seems that the problem is that @blueprintjs/core augments tether, but does not have a dependency on @types/tether in package.json.

Installing the @types/tether should avoid this error. but really the fix should be in @blueprintjs/core package.json.

So devs must add that package. See microsoft/TypeScript#10522

[adidahiya]

Interesting... thanks for doing that debugging @Ciantic. A missing dependency on @types/tether also came up here: #201 (comment). I generally agree that we should add that as a dependency in package.json despite that fact that it will be superfluous for JS-only consumers.

[adidahiya]

@types/tether was added as a dependency in #360.

[codebling]

@adidahiya only @types/dom4 was added in 360, and only to core.

Haven't been following the whole discussion but @types/tether has been around for a while.

[adidahiya]

whoops, you're right. @types/tether is a dependency for this monorepo, but not in core. still needs to be added.

[llorca]

Seems super straightforward, let's do it for 1.4.0 this week in addition to the SSR stuff

[forman]

Thanks!