fix: pass transformers object to ts.transpileModule method (Fixes #1051)

[thetutlage]

As per the README, only the transformers factory function is not allowed during the transpileOnly module. However, an object can still be passed.

In this PR https://github.com/TypeStrong/ts-node/pull/879/files#diff-f41e9d04a45c83f3b6f6e630f10117feR383, the code already guards against the factory function, but doesn't pass the transformers to the transpileModule method.

Related issue #1051

[codecov]

Codecov Report

Merging #1054 into master will not change coverage.
The diff coverage is n/a.

@@ Coverage Diff @@## master #1054 +/- ##
=======================================
Coverage 74.83% 74.83% =======================================
Files 6 6 Lines 608 608 Branches 142 142 =======================================
Hits 455 455 Misses 100 100 Partials 53 53 

Flag	Coverage Δ
#node_10	72.26% <0.00%> (ø)
#node_12_15	72.65% <0.00%> (ø)
#node_12_16	72.65% <0.00%> (ø)
#node_13	74.67% <0.00%> (ø)
#node_14	74.67% <0.00%> (ø)
#typescript_2_7	74.34% <0.00%> (ø)
#typescript_latest	73.51% <0.00%> (ø)
#typescript_next	73.35% <0.00%> (ø)
#ubuntu	74.50% <0.00%> (ø)
#windows	74.67% <0.00%> (ø)

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[coveralls]

Coverage increased (+1.03%) to 83.019% when pulling a6aa25b on thetutlage:master into e567002 on TypeStrong:master.

[cspotcode]

@thetutlage Thanks for the speedy PR!

What is the reason for moving the assertion into getOutputTranspileOnly? If I'm reading the change correctly, this change delays the TypeError so it's no longer thrown by register() or create() but is instead thrown by require() calls.

[thetutlage]

The main reason for moving the typeof transformers === 'function' check inside the getOutputTranspileOnly method is to narrow down the transformers type.

Inside getOutputTranspileOnly the transformers variable is typed as follows

Now, in order to narrow it down, we have two options

• Move the if condition inside this method (like I did)
• Manually type cast transformers to Exclude the factory function

What you think?

[cspotcode]

Using a type assertion makes more sense. We need to keep the assertion where it was because that's the more intuitive place for a `TypeError` to be thrown. It makes the API better.

…

On Sun, May 24, 2020, 2:06 AM Harminder Virk ***@***.***> wrote: The main reason for moving the typeof transformers === 'function' check inside the getOutputTranspileOnly method is to narrow down the transformers type. Inside getOutputTranspileOnly the transformers variable is typed as follows [image: Screen Shot 2020-05-24 at 11 33 36 AM] <https://user-images.githubusercontent.com/1706381/82746917-7cb1fb80-9db2-11ea-8c72-1ab78ad0105e.png> Now, in order to narrow it down, we have two options - Move the if condition inside this method (like I did) - Manually type cast transformers to Exclude the factory function What you think? — You are receiving this because you commented. Reply to this email directly, view it on GitHub <#1054 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAC35OBIUXYWDVYN6C4DIC3RTC2ORANCNFSM4NIPHT2Q> .

[thetutlage]

If I get it right, you are saying to move the typeof check to its original place (where it was earlier) and instead go with 2nd option, ie: Manually type cast transformers to Exclude the factory function

Right?

[cspotcode]

Correct.

…

On Sun, May 24, 2020, 5:05 AM Harminder Virk ***@***.***> wrote: If I get it right, you are saying to move the typeof check to its original place (where it was earlier) and instead go with 2nd option, ie: Manually type cast transformers to Exclude the factory function Right? — You are receiving this because you commented. Reply to this email directly, view it on GitHub <#1054 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAC35OHXOUIKLUFQ5VVVA4TRTDPN3ANCNFSM4NIPHT2Q> .

[thetutlage]

Does it look fine now?

[cspotcode]

Sweet, looks great!

[blakeembrey]

@cspotcode Is there any reason we shouldn't move the getOutputTranspileOnly function back within the else block?

[cspotcode]

No reason. Yeah, we should move it back. I'll do that here and merge.

…

On Mon, May 25, 2020, 1:02 PM Blake Embrey ***@***.***> wrote: ***@***.**** approved this pull request. @cspotcode <https://github.com/cspotcode> Is there any reason we shouldn't move the getOutputTranspileOnly function back within the else block? — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#1054 (review)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAC35OFF2NKXPZM37GR4T4LRTKQDRANCNFSM4NIPHT2Q> .

[cspotcode]

Nevermind, I'm going to do it as a separate PR, cuz it'll be clearer that way.

[thetutlage]

@cspotcode Any idea when this will be released?

[cspotcode]

No set date; maybe this weekend? Depends when someone has time; work is keeping me busy this month. In the meantime, you can install off of master (npm can install straight from git) or downgrade to an older version.

…

On Tue, Jun 2, 2020 at 10:49 AM Harminder Virk ***@***.***> wrote: @cspotcode <https://github.com/cspotcode> Any idea when this will be released? — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#1054 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAC35OAPTEUGJQJKV4XSTVDRUUGOPANCNFSM4NIPHT2Q> .