Some Eclipse Foundation services are deprecated, or will be soon. Please ensure you've read this important communication.

Bug 495822

Summary:	[tern][eslint] Guessed types should not be flagged as problems in the no-undef-expression rule
Product:	[ECD] Orion	Reporter:	Michael Rennie <Michael_Rennie>
Component:	JS Tools	Assignee:	Michael Rennie <Michael_Rennie>
Status:	RESOLVED FIXED	QA Contact:
Severity:	normal
Priority:	P3	CC:	curtis.windatt.public, Olivier_Thomann
Version:	10.0	Flags:	Olivier_Thomann: review+ curtis.windatt.public: review+
Target Milestone:	12.0
Hardware:	PC
OS:	Windows 7
Whiteboard:

Description Michael Rennie

2016-06-09 13:29:57 EDT

When we ask for a type from Tern, sometimes it will guess (OK), and sometimes the guess is correct (and sometimes not).

In our linting rule no-undef-expression, if it guesses and gets it wrong we end up marking the member expression anyway. We should ignore guessed types by default, as mis-marked expressions cause loss of trust in the tools.

Comment 1 Michael Rennie

2016-06-09 13:32:38 EDT

A real life example of this is in server.js - electron.app.* all get flagged as not being part of 'express'.

Comment 2 Michael Rennie

2016-06-09 14:09:22 EDT

Fix + tests:

http://git.eclipse.org/c/orion/org.eclipse.orion.client.git/commit/?id=0032b1c3caffe5be54c64cf388c33065f3aea988

Curtis, Olivier, please review.

Comment 3 Olivier Thomann

2016-06-09 14:23:11 EDT

+1

Comment 4 Curtis Windatt

2016-06-09 14:30:11 EDT

+1

I don't think that we should be checking the guess flag on the first findTypeExpr result.  If we are guessing a type but then can't find the prop, we should fall into the second check (check the type of the object).  However, in practice this case should never come up (if we get a guessed type information we should always be able to find the matching prop).