Environment Variables

HG
Path to the 'hg' executable, automatically passed when running hooks, extensions or external tools. If unset or empty, this is the hg executable's name if it's frozen, or an executable named 'hg' (with %PATHEXT% [defaulting to COM/EXE/BAT/CMD] extensions on Windows) is searched.
HGEDITOR

This is the name of the editor to run when committing. See EDITOR.

(deprecated, see hg help config.ui.editor)

HGENCODING
This overrides the default locale setting detected by Mercurial. This setting is used to convert data including usernames, changeset descriptions, tag names, and branches. This setting can be overridden with the --encoding command-line option.
HGENCODINGMODE
This sets Mercurial's behavior for handling unknown characters while transcoding user input. The default is "strict", which causes Mercurial to abort if it can't map a character. Other settings include "replace", which replaces unknown characters, and "ignore", which drops them. This setting can be overridden with the --encodingmode command-line option.
HGENCODINGAMBIGUOUS
This sets Mercurial's behavior for handling characters with "ambiguous" widths like accented Latin characters with East Asian fonts. By default, Mercurial assumes ambiguous characters are narrow, set this variable to "wide" if such characters cause formatting problems.
HGMERGE

An executable to use for resolving merge conflicts. The program will be executed with three arguments: local file, remote file, ancestor file.

(deprecated, see hg help config.ui.merge)

HGRCPATH

A list of files or directories to search for configuration files. Item separator is ":" on Unix, ";" on Windows. If HGRCPATH is not set, platform default search path is used. If empty, only the .hg/hgrc from the current repository is read.

For each element in HGRCPATH:

  • if it's a directory, all files ending with .rc are added
  • otherwise, the file itself will be added
HGPLAIN

When set, this disables any configuration settings that might change Mercurial's default output. This includes encoding, defaults, verbose mode, debug mode, quiet mode, tracebacks, and localization. This can be useful when scripting against Mercurial in the face of existing user configuration.

In addition to the features disabled by HGPLAIN=, the following values can be specified to adjust behavior:

+strictflags
Restrict parsing of command line flags.

Equivalent options set via command line flags or environment variables are not overridden.

See hg help scripting for details.

HGPLAINEXCEPT

This is a comma-separated list of features to preserve when HGPLAIN is enabled. Currently the following values are supported:

alias
Don't remove aliases.
color
Don't disable colored output.
i18n
Preserve internationalization.
revsetalias
Don't remove revset aliases.
templatealias
Don't remove template aliases.
progress
Don't hide progress output.

Setting HGPLAINEXCEPT to anything (even an empty string) will enable plain mode.

HGUSER

This is the string used as the author of a commit. If not set, available values will be considered in this order:

  • HGUSER (deprecated)
  • configuration files from the HGRCPATH
  • EMAIL
  • interactive prompt
  • LOGNAME (with @hostname appended)

(deprecated, see hg help config.ui.username)

EMAIL
May be used as the author of a commit; see HGUSER.
LOGNAME
May be used as the author of a commit; see HGUSER.
VISUAL
This is the name of the editor to use when committing. See EDITOR.
EDITOR
Sometimes Mercurial needs to open a text file in an editor for a user to modify, for example when writing commit messages. The editor it uses is determined by looking at the environment variables HGEDITOR, VISUAL and EDITOR, in that order. The first non-empty one is chosen. If all of them are empty, the editor defaults to 'vi'.
PYTHONPATH
This is used by Python to find imported modules and may need to be set appropriately if this Mercurial is not installed system-wide.