Refactor Go code using Comby


This batch change uses Sourcegraph's structural search and Comby to rewrite Go statements from

fmt.Sprintf("%d", number)



The statements are semantically equivalent, but the latter is clearer.

Since the replacements could require importing the strconv package, it uses goimports to update the list of imported packages in all *.go files.


We recommend that use the latest version of Sourcegraph when working with Batch Changes and that you have a basic understanding of how to create batch specs and run them. See the following documents for more information:

  1. "Quickstart"
  2. "Introduction to Batch Changes"

Create the batch spec

Save the following batch spec YAML as sprintf-to-itoa.batch.yaml:

name: sprintf-to-itoa
description: |
  This batch change uses [Comby]( to replace `fmt.Sprintf` calls
  in Go code with the equivalent but clearer `strconv.Iota` call.  

  - repositoriesMatchingQuery: lang:go fmt.Sprintf("%d", :[v]) patterntype:structural

  - run: comby -in-place 'fmt.Sprintf("%d", :[v])' 'strconv.Itoa(:[v])' .go -matcher .go -exclude-dir .,vendor
    container: comby/comby
  - run: goimports -w $(find . -type f -name '*.go' -not -path "./vendor/*")
    container: unibeautify/goimports

  title: Replace fmt.Sprintf with equivalent strconv.Itoa
  body: This batch change replaces `fmt.Sprintf` with `strconv.Itoa`
  branch: batch-changes/sprintf-to-itoa
    message: Replacing fmt.Sprintf with strconv.Iota
  published: false

Create the batch change

  1. In your terminal, run this command:

    src batch preview -f sprintf-to-itoa.batch.yaml
  2. Wait for it to run and compute the changes for each repository.

  3. Open the preview URL that the command printed out.

  4. Examine the preview. Confirm that the changesets are the ones you intended to track. If not, edit the batch spec and then rerun the command above.

  5. Click the Apply button to create the batch change.

  6. Feel free to then publish the changesets (i.e. create pull requests and merge requests) by modifying the published attribute in the batch spec and re-running the src batch preview command.