Red Hat SummitChapter 3. The gofmt formatting tool
Instead of a style guide, the Go programming language uses the gofmt code formatting tool. gofmt automatically formats your code according to the Go layout rules.
3.1. Prerequisites
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Go Toolset is installed.
For more information, see Installing Go Toolset.
3.2. Formatting code
You can use the gofmt formatting tool to format code in a given path. When the path leads to a single file, the changes apply only to the file. When the path leads to a directory, all .go files in the directory are processed.
Procedure
To format your code in a given path, run:
On Red Hat Enterprise Linux 8:
$ gofmt -w <code_path>-
Replace
<code_path>with the path to the code you want to format.
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Replace
On Red Hat Enterprise Linux 9:
$ gofmt -w <code_path>-
Replace
<code_path>with the path to the code you want to format.
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Replace
To print the formatted code to standard output instead of writing it to the original file, omit the -w option.
3.3. Previewing changes to code
You can use the gofmt formatting tool to preview changes done by formatting code in a given path. The output in unified diff format is printed to standard output.
Procedure
To show differences in your code in a given path, run:
On Red Hat Enterprise Linux 8:
$ gofmt -w -d <code_path>-
Replace
<code_path>with the path to the code you want to compare.
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Replace
On Red Hat Enterprise Linux 9:
$ gofmt -w -d <code_path>-
Replace
<code_path>with the path to the code you want to compare.
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Replace
3.4. Simplifying code
You can use the gofmt formatting tool to simplify your code.
Procedure
To simplify anf format code in a given path, run:
On Red Hat Enterprise Linux 8:
$ gofmt -s -w <code_path>-
Replace
<code_path>with the path to the code you want to simplify.
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Replace
On Red Hat Enterprise Linux 9:
$ gofmt -s -w <code_path>-
Replace
<code_path>with the path to the code you want to simplify.
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Replace
3.5. Refactoring code
You can use the gofmt formatting tool to refactor your code by applying arbitrary substitutions.
Procedure
To refactor and format your code in a given path, run:
On Red Hat Enterprise Linux 8:
$ gofmt -r -w <rewrite_rule> <code_path>
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Replace
<code_path>with the path to the code you want to refactor and<rewrite_rule>with the rule you want it to be rewritten by.
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Replace
On Red Hat Enterprise Linux 9:
$ gofmt -r -w <rewrite_rule> <code_path>
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Replace
<code_path>with the path to the code you want to refactor and<rewrite_rule>with the rule you want it to be rewritten by.
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Replace
