Configuration from .json file

[davglass]

It would be really nice to drive some things in Istanbul with a json file.

• Custom tolerances for coverage warnings
• Output directory
• Possible theme location

Istanbul should also walk up the directory tree looking for the json file, if it's not found then use the defaults.

Potentially, it could also look for a package.json file, if found, parse it and check for an istanbul key and use that as the configuration.

[deepsweet]

+1 but with .istanbul.yml

[robkinyon]

It would be awesome if report/html.js:getReportClass() would pull the 80 and 50 for the high/medium/low coloring from this file. I might want a specific project to have a 90% green and 75% yellow instead of 80/50.

It would be even cooler if I could specify 90/75 for functions, but 80/50 for lines (or something).

[gotwarlost]

Yes, that would be the way this feature would work when implemented. "when implemented" does not map to a timeline :)

here is a strawman design:

https://github.com/gotwarlost/istanbul/blob/master/misc/config/istanbul-config-alt.json

[gotwarlost]

Added.

$ istanbul help config

Configuring istanbul
====================

 istanbul can be configured globally using a .istanbul.yml YAML file at the
 root of your source tree. Every command also accepts a --config=<config-file>
 argument to customize its location per command. The alternate config file can
 be in YAML, JSON or node.js (exporting the config object).

 The config file currently has three sections for instrumentation, reporting
 and hooks. Note that certain commands (like `cover`) use information from
 multiple sections.

 Keys in the config file usually correspond to command line parameters with the
 same name. The verbose option for every command shows you the exact
 configuration used

The default configuration is as follows:

verbose: false
instrumentation:
    root: .
    default-excludes: true
    excludes: []
    embed-source: false
    variable: __coverage__
    compact: true
    preserve-comments: false
    complete-copy: false
    save-baseline: false
    baseline-file: ./coverage/coverage-baseline.json
reporting:
    print: summary
    reports:
        - lcov
    dir: ./coverage
    watermarks:
        statements: [50, 80]
        lines: [50, 80]
        functions: [50, 80]
        branches: [50, 80]
hooks:
    hook-run-in-context: false
    post-require-hook: null


 The `watermarks` section does not have a command line equivalent. It allows
 you to set up low and high watermark percentages for reporting. These are
 honored by all reporters that colorize their output based on low/ medium/ high
 coverage