Regular expression based version read/write plugin for release-it

This release-it plugin reads and/or writes versions using regular expressions.

When reading, the regular expression is used to find and extract the current version from a file.

When writing, the regular expressions are used to find the places where the new version is inserted. In fact, it is possible to insert more than just the new version. See the configuration options below for details.

⚠️ Note:
Version 5 and later of release-it-regex-bumper require version 16 or later of release-it.
When you are using release-it version 15.x or earlier, then use release-it-regex-bumper version 4.x or earlier.

npm install --save-dev @j-ulrich/release-it-regex-bumper

To use the RegEx Bumper, configure it in the plugins object of the release-it configuration.

For example:

{
    "plugins": {
        "@j-ulrich/release-it-regex-bumper": {
            "in": "path/to/version_file.txt",
            "out": [
                "path/to/version_file.txt",
                {
                    "file": "README.md",
                    "search": "Version \\d+\\.\\d+\\.\\d+",
                    "replace": "Version {{versionWithoutPrerelease}}"
                }
            ]
        }
    }
}

For a more complex example, see here.

RegEx bumper uses XRegExp. This means that the search and replace options can make use of the extended features of XRegExp like backreferences to named capturing groups, the s flag etc.

Since the plugin's configuration is written in JSON format, remember to properly escape backslashes inside the regular expression patterns as needed in JSON strings (double the backslashes). So for example, the pattern \d+ needs to be written as "\\d+" inside JSON.

ℹ️ Note:
Options without a default value are required.

Type: string|object
Default: null

The in option defines where and how to read the current version. If this option is defined and not null, the version from this file will take precedence over the version from package.json or the latest Git tag (which release-it uses by default).

If in is a string, it is interpreted as the path to the file where the current version is read from. The global search pattern is then used to find the version in the file.

If in is an object, it takes the following properties:

Type: string

Path to the file where the current version is read from.

Type: string
Default: null

Encoding to be used when reading in.file. The supported encodings are the ones supported by Node's fs module. If this option is null or not defined, the global encoding option is used.

Type: string|object
Default: null

Defines the regular expression to find the version inside the in.file. If this option is null or not defined, the global search option is used.

If in.search is a string, it is interpreted as the regular expression pattern.

If in.search is an object, it takes the following properties:

Type: string

The regular expression pattern template to find the version inside in.file.

Capturing groups can be used to extract the version from a part of the whole match. See the documentation of the configuration option in.search.versionCaptureGroup for a description of the handling of capturing groups.

The in.search.pattern also supports a set of placeholders (since version 3.0.0):

• {{semver}} is matching any version string complying to the semantic versioning specification (meaning at least "major.minor.patch").
• {{now:<format>}} is matching the current timestamp in a format specified by the <format> parameter. The supported format syntax can be found in the date-fns format documentation.
  Example: {{now:yyyy-MM-dd}}
• {{{}} is matching a literal {. This can be used to match a literal placeholder.
  For example: {{{}}{foo}} is matching {{foo}}

ℹ️ Note:
All the placeholders are contained in a non-capturing group ((?:...)) so they behave like "atomic" constructs.

Type: string
Default: null

The flags for the regular expression in.search.pattern.

If this option is null or not defined, the global search.flags are used.

Type: integer|string
Default: null

Defines the capture group from the in.search.pattern which matches the version. If the in.search.pattern contains (named) capturing groups, use this option to define which group matches the version. If in.search.pattern does not contain a capturing group with the name or index defined by this option, this option is ignored and the whole match is used as version.

If this option is null or not defined, the global search.versionCaptureGroup is used.

If both, this option and the global search.versionCaptureGroup are null (the default), then the capturing group with name version is used if it exists. Else the capturing group with index 1 is used if it exists. Else the whole match is used.

Type: string|object|array<string|object>
Default: null

The out option defines where and how to write the new version. If defined and not null, the version information will be written to the matches of the regular expressions in the specified file(s).

If out is an array, the entries are processed one after another and each entry is treated like described below when out itself is a string or an object.

If out is a string, it is interpreted as the path to the file where the new version is written to. The global search and replace options are used in this case to find and replace the version information.

If out is an object, it takes the following properties:

Type: string
Default: null but either this option or out.files (or both) must contain a value

The path to the file where the new version is written to.

The out.file option is parsed with fast-glob, so glob patterns can be used to match multiple files to write to:

"plugins": {
    "@j-ulrich/release-it-regex-bumper": {
        "out": {
            "file": "dist/*.json",
            "search": "\"version\":\\s*\"([0-9.]+)\"",
            "replace": "\"version\": \"{{version}}\""
        }
    }
}

If both, this option and out.files are given, both are processed.

Type: string|array<string>
Default: null but either this option or out.file (or both) must contain a value
Since: 1.1.0

A path or an array of paths to files where the new version is written to. This option behaves the same as the out.file option but allows specifying multiple files or patterns. Accordingly, the entries are also parsed with fast-glob:

"plugins": {
    "@j-ulrich/release-it-regex-bumper": {
        "out": {
            "files": [ "**/*.json", "**/*.yml" ],
            "search": "\"version\":\\s*\"([0-9.]+)\"",
            "replace": "\"version\": \"{{version}}\""
        }
    }
}

If both, this option and out.file are given, both are processed.

Type: string
Default: null

Encoding to be used when reading and writing out.file. The supported encodings are the ones supported by Node's fs module. If this option is null or not defined, the global encoding option is used.

Type: string|object
Default: null

Defines the regular expression to find the text which is replaced with the new version inside out.file. If this option is null or not defined, the global search is used.

If out.search is a string, it is interpreted as the regular expression pattern.

If out.search is an object, it takes the following properties:

Type: string

The regular expression pattern template to find the text to be replaced with the new version inside out.file.

In contrast to in.search.pattern, capturing groups are not treated special in this pattern. So out.replace always replaces the whole match.

If this option is null or not defined, the global search resp. global search.pattern is used.

The out.search.pattern also supports a set of placeholders (since version 3.0.0):

• {{version}} is matching the current version (before the increment).
• {{major}} is matching the major part of the current version.
• {{minor}} is matching the minor part of the current version.
• {{patch}} is matching the patch part of the current version.
• {{prerelease}} is matching the prerelease part of the current version. If the version does not have a prerelease part, it is omitted (matching empty string).
• {{prefixedPrerelease}} is matching a dash ('-') followed by the prerelease part of the current version. If the version does not have a prerelease part, it is omitted (matching empty string).
• {{build}} is matching the build part of the current version. If the version does not have a build part, it is omitted (matching empty string).
• {{prefixedBuild}} is matching a plus ('+') followed by the build part of the current version. If the version does not have a build part, it is omitted (matching empty string).
• {{versionWithoutBuild}} is matching the current version without the build part.
• {{versionWithoutPrerelease}} is matching the current version without the prerelease and build parts.
• {{tag}} is matching the current VCS tag (before the bump).
• {{newVersion}} is matching the new version (after the increment).
• {{semver}} is matching any version string complying to the semantic versioning specification (meaning at least "major.minor.patch").
• {{now:<format>}} is matching the current timestamp in a format specified by the <format> parameter. The supported format syntax can be found in the date-fns format documentation.
  Example: {{now:yyyy-MM-dd}}
• {{{}} is matching a literal {. This can be used to match a literal placeholder.
  For example: {{{}}{foo}} is matching {{foo}}

ℹ️ Note:
All the placeholders are contained in a non-capturing group ((?:...)) so they behave like "atomic" constructs.

Type: string
Default: null

The flags for the regular expression out.search.pattern.

If this option is null or not defined, the global search.flags are used.

Type: string
Default: null

The template string which replaces the matches of out.search inside out.file. If this option is null or not defined, the global replace option is used.

The template string can reference capturing groups from out.search with the syntax $n where n is the number of the referenced capturing group or with ${n} where n is the name or number of a capturing group. For the complete syntax see the documentation of XRegExp.

The template string also supports a set of placeholders:

• {{version}} is replaced by the new version.
• {{major}} is replaced by the major part of the new version.
  Since: 1.2.0
• {{minor}} is replaced by the minor part of the new version.
  Since: 1.2.0
• {{patch}} is replaced by the patch part of the new version.
  Since: 1.2.0
• {{prerelease}} is replaced by the prerelease part of the new version or an empty string if the version does not have a prerelease part.
  Since: 1.2.0
• {{prefixedPrerelease}} is replaced by a dash ('-') followed by the prerelease part of the new version or an empty string if the version does not have a prerelease part.
  Since: 3.0.0
• {{build}} is replaced by the build part of the new version or an empty string if the version does not have a build part.
  Since: 1.2.0
• {{prefixedBuild}} is replaced by a plus ('+') followed by the build part of the new version or an empty string if the version does not have a build part.
  Since: 3.0.0
• {{versionWithoutBuild}} is replaced by the new version without the build part.
  Since: 1.2.0
• {{versionWithoutPrerelease}} is replaced by the new version without the prerelease and build parts.
  Since: 1.2.0
• {{latestVersion}} is replaced by the current version, that is the version before the increase.
• {{latestTag}} is replaced by the current VCS tag.
• {{now}} is replaced by the current timestamp in ISO 8601 format.
• {{now:<format>}} is replaced by the current timestamp in a format specified by the <format> parameter. The supported format syntax can be found in the date-fns format documentation.
  Example: {{now:yyyy-MM-dd}}
• {{{}} is replaced by a literal {. This can be used to write a literal placeholder.
  For example: {{{}}{foo}} is replaced by {{foo}}
  Since: 1.2.0

The placeholders are replaced before the template string is used in the search and replace and thus before the capturing group references are replaced.

Type: string|object
Default: An object with the default values as described below.

Defines the default regular expression to be used when no in.search or out.search is given.

If this option is not defined or set to null, the default value is used.

If search is a string, it is interpreted as the regular expression pattern.

If search is an object, it takes the following properties:

Type: string
Default: "{{semver}}"

The default regular expression pattern template which is used when in.search.pattern or out.search.pattern is null or not defined. See in.search.pattern and out.search.pattern for more information.

⚠️ Warning:
Note that the global search.pattern is used for both in.search.pattern and out.search.pattern unless overridden explicitly. But in.search.pattern does not support all the placeholders of out.search.pattern and using unsupported placeholders raises an error.

If this option is not defined or set to null, the default value is used.

Type: string
Default: null

The default flags for the search pattern which are used when in.search.flags or out.search.flags are null or not defined.

Type: integer|string
Default: null

Defines the default capture group which is used when in.search.versionCaptureGroup is null or not defined.

Note that this property applies only when search is used for reading the current version and has no effect when writing the new version.

Type: string
Default: "{{version}}"

The default template string used when out.replace is null or not defined. See out.replace for more information.

If this option is not defined or set to null, the default value is used.

Type: string
Default: "utf-8"

The default encoding used when in.encoding or out.encoding is null or not defined. The supported encodings are the ones supported by Node's fs module.

If this option is not defined or set to null, the default value is used.

To completely disable changing any files by the plugin, you can use the command-line parameter --no-plugins.@j-ulrich/release-it-regex-bumper.out. For example:

npx release-it --no-plugins.@j-ulrich/release-it-regex-bumper.out

Copyright (c) 2020-2025 Jochen Ulrich

Licensed under MIT license.