https://github.com/quartzbio/r-coverage-patch

Patches to add code coverage support in the R interpreter.
https://github.com/quartzbio/r-coverage-patch

Last synced: about 2 months ago
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Patches to add code coverage support in the R interpreter.

• Host: GitHub
• URL: https://github.com/quartzbio/r-coverage-patch
• Owner: quartzbio
• License: gpl-3.0
• Archived: true
• Created: 2014-12-15T14:50:30.000Z (over 9 years ago)
• Default Branch: master
• Last Pushed: 2014-12-16T16:37:09.000Z (over 9 years ago)
• Last Synced: 2024-01-28T05:03:50.599Z (5 months ago)
• Language: C
• Size: 516 KB
• Stars: 3
• Watchers: 4
• Forks: 0
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

Lists

• AwesomeInterpreter - r-coverage-patch

README

        
r-coverage-patch

================

Patches to add code coverage support in the R interpreter.

## Overview

This repository contains patches of the [R](http://www.r-project.org/) interpreter source code to add [code coverage](http://en.wikipedia.org/wiki/Code_coverage) support. 

It allows to know which exact lines of source code were exercized/hit/covered while running some piece of code (usually a test suite).

The easiest way to test it is using our docker container: https://github.com/quartzbio/r-coverage-docker

## Installation

As stated above, you can just use the docker container.

To patch it manually:

 1. choose the appropriate patch corresponding to the version of the R interpreter you are going to use.

 1. get the source code of the R version (download and untar)

 2. patch the source code (patch)

 3. configure the source directory (./configure)

 4. compile and install (make; make install)

The project is organized in sudirectories per supported R version, e.g. r302 for R version 3.0.2.

The above steps are somewhat automated using a Makefile (you need probably GNU make).

For example, to download, untar, patch, configure, make and install R-3.0.2:

```bash

git clone https://github.com/quartzbio/r-coverage-patch.git

cd r-coverage-patch/r302/

# download, untar and patch

make apply_production_patch 

# install in ./local/

make install 

# Or install in a custom place

make install PREFIX=/whatever/

# run it

./local/bin/R

```

## Implementation

I added a condition in the internal C function **getSrcref()**, that records the line numbers if the code

coverage is started (via Rcov_start()).

The overhead should be minimal since for a given file, subsequent covered lines will be stored

in constant time. 

I use a hashed env to store the occurrences by file.

I added two entry points in the utils package (**Rcov_start()** and **Rcov_stop()**)

### viewing the main patched file: eval.c

For convenience (Caution: it can be outdated), I included the main patched file in the repo, 

you can view it here: https://github.com/quartzbio/r-coverage-patch/blob/master/r302/patched_files/eval.c

## Usage 

(see also https://github.com/quartzbio/r-coverage-docker#usage).

Start the patched R interpreter, then:

```r

library(devtools)

pkg  <- download.packages('testthat', '.', repos = "http://stat.ethz.ch/CRAN")

untar(pkg[1, 2])

Rcov_start()

test('testthat')

res <- as.list(Rcov_stop())

print(res)

```