Enabling nyc to generate reports from coverage.raw.json

Hi, I’d like to make a feature request.

If nyc can generate reports by only reading coverage.json, then it’d be convenient.

[ansjcy]

After trying multiple nyc commands to produce the report from JSON with no luck, I found an interesting behavior of nyc: You have to be in the parent directory of the instrumented code when you are generating a report. For example: If the code I instrumented is in /usr/share/node/**, and the merged coverage.json result is in /tmp directory. If I run nyc report --temp-dir=/tmp --reporter=text under /tmp, I won’t get anything.

----------|---------|----------|---------|---------|-------------------
File      | % Stmts | % Branch | % Funcs | % Lines | Uncovered Line #s
----------|---------|----------|---------|---------|-------------------
All files |       0 |        0 |       0 |       0 |
----------|---------|----------|---------|---------|-------------------

But if I run the same command under /usr/share/node or /, I’m able to get the correct output with coverage numbers. Not sure if it’s a weird permission issue in nyc.

[jjangga0214]

@coreyfarrell I just read nyc’s docs first time a few days ago. To me, it was unclear that nyc can generate reports from coverage.json.

For more reader-friendly docs(and for folks who do not know .nyc_output), how do you think an explicit mention on this feature with practical command usage example (like below)?

# this reads json coverage files from ./dir-containing-coverage-json 
# and generate html report
# to ./dir-for-report
nyc report \
  --temp-dir ./dir-containing-coverage-json \
  --reporter html \
  --report-dir ./dir-for-report