jashkenas / jashkenas/coffeescript

Bug: Poor error message for invalid use of `then` keyword

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bug
Dominant language
CoffeeScript
Stars
16.6k
Forks
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PR merge metrics
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Description

Input Code
then
Expected Behavior
[stdin]:1:1: error: unexpected then
then
^^^^
Current Behavior
TypeError: Cannot read properties of undefined (reading '2')
Context

This is very minor but thought I'd point it out.

https://coffeescript.org/#try:then

  • CoffeeScript version: 2.7.1

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First steps

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Research direction

Reproduce the issue with the then input using the linked CoffeeScript try page and compare the current TypeError with the expected compiler diagnostic. Trace the parser or error-reporting entry point that handles this invalid keyword, then verify that the displayed message and source location match the expected output.

Written by the indexing model from the issue text.

Assessment

Tech stack
coffeescript
Domain
compilers
Issue type
Bug
Difficulty
3/5
Estimated time
1-2 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
45/100

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