Linux

Combine operating system and Linux distribution conditionals

There can be as much variation between Linux distributions as there is between operating systems. Due to text/template's eager evaluation of conditionals, this means you often have to write templates with nested conditionals:

{{ if eq .chezmoi.os "darwin" }}
# macOS-specific code
{{ else if eq .chezmoi.os "linux" }}
{{   if eq .chezmoi.osRelease.id "debian" }}
# Debian-specific code
{{   else if eq .chezmoi.osRelease.id "fedora" }}
# Fedora-specific code
{{   end }}
{{ end }}

This can be simplified by combining the operating system and distribution into a single custom template variable. Put the following in your configuration file template:

{{- $osid := .chezmoi.os -}}
{{- if hasKey .chezmoi.osRelease "id" -}}
{{-   $osid = printf "%s-%s" .chezmoi.os .chezmoi.osRelease.id -}}
{{- end -}}

[data]
    osid = {{ $osid | quote }}

This defines the .osid template variable to be {{ .chezmoi.os }} on machines without an os-release file, or to be {{ .chezmoi.os }}-{{ .chezmoi.osRelease.id }} on machines with an os-release file.

You can then simplify your conditionals to be:

{{ if eq .osid "darwin" }}
# macOS-specific code
{{ else if eq .osid "linux-debian" }}
# Debian-specific code
{{ else if eq .osid "linux-fedora" }}
# Fedora-specific code
{{ end }}