avajs/ava

Support placeholder tokens in t.log()

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#1,654 opened on Jan 25, 2018

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 (2 comments) (0 reactions) (0 assignees)JavaScript (20,600 stars) (1,408 forks)batch import
enhancementhelp wantedscope:test-interface

Description

t.log() is modeled after console.log(), which in Node.js uses util.format(). This function supports placeholder tokens. I couldn't quite find a maintained & ready module that would let us support the same tokens.

This is the behavior I'd expect:

Token Behavior
%s Cast the value to a string
%d Cast the value to a number
%i Parse the value as an integer
%f Parse the value as a float
%j Stringify the value as JSON, but output '[Circular]' if it contains circular references
%o Stringify using Concordance (current behavior since #1653)
%O Stringify using Concordance (current behavior since #1653)
%% Print '%'

Contributor guide

Tech stack
javascriptnodejs
Domain
testing
Issue type
feature
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
3
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-3 hours
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
fresh
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
clear
Prerequisites
basic JavaScriptunderstanding of console.log formatting
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
70
Research direction
Investigate the current implementation of `t.log()` in AVA (likely in `lib/test.js` or similar). Look at how `util.format` works in Node.js and consider implementing a simple formatter that supports `%s`, `%d`, `%i`, `%f`, `%j`, `%o`, `%O`, and `%%` tokens. Check for existing modules like `printf` or `sprintf js` but note that `util.format` is built in and may suffice. Also review the Concordance integration (from PR #1653) to ensure `%o` and `%O` behave as expected. No linked PRs or comments suggest dependencies. The issue is clear and unclaimed, making it suitable for a first time contributor.
Support placeholder tokens in t.log() · avajs/ava#1654 | Good First Issue