Don't override customized environments in subshells

Only set up environment for the top-level shell, and allow it to be
inherited normally.

A top level shell is usually a login shell, but can also be a
non-interactive, non-login shell in certain cases, such as when
executing an SSH remote command.

Signed-off-by: Sorin Ionescu <sorin.ionescu@gmail.com>

runcoms/zprofile

@@ -5,3 +5,72 @@
 #   Sorin Ionescu <sorin.ionescu@gmail.com>
 #
 
+#
+# Browser
+#
+
+if [[ "$OSTYPE" == darwin* ]]; then
+  export BROWSER='open'
+fi
+
+#
+# Editors
+#
+
+export EDITOR='nano'
+export VISUAL='nano'
+export PAGER='less'
+
+#
+# Language
+#
+
+if [[ -z "$LANG" ]]; then
+  export LANG='en_US.UTF-8'
+fi
+
+#
+# Paths
+#
+
+typeset -gU cdpath fpath mailpath path
+
+# Set the the list of directories that cd searches.
+# cdpath=(
+#   $cdpath
+# )
+
+# Set the list of directories that Zsh searches for programs.
+path=(
+  /usr/local/{bin,sbin}
+  $path
+)
+
+#
+# Less
+#
+
+# Set the default Less options.
+# Mouse-wheel scrolling has been disabled by -X (disable screen clearing).
+# Remove -X and -F (exit if the content fits on one screen) to enable it.
+export LESS='-F -g -i -M -R -S -w -X -z-4'
+
+# Set the Less input preprocessor.
+if (( $+commands[lesspipe.sh] )); then
+  export LESSOPEN='| /usr/bin/env lesspipe.sh %s 2>&-'
+fi
+
+#
+# Temporary Files
+#
+
+if [[ ! -d "$TMPDIR" ]]; then
+  export TMPDIR="/tmp/$USER"
+  mkdir -p -m 700 "$TMPDIR"
+fi
+
+TMPPREFIX="${TMPDIR%/}/zsh"
+if [[ ! -d "$TMPPREFIX" ]]; then
+  mkdir -p "$TMPPREFIX"
+fi
+

runcoms/zshenv

@@ -5,72 +5,8 @@
 #   Sorin Ionescu <sorin.ionescu@gmail.com>
 #
 
-#
-# Browser
-#
-
-if [[ "$OSTYPE" == darwin* ]]; then
-  export BROWSER='open'
-fi
-
-#
-# Editors
-#
-
-export EDITOR='nano'
-export VISUAL='nano'
-export PAGER='less'
-
-#
-# Language
-#
-
-if [[ -z "$LANG" ]]; then
-  export LANG='en_US.UTF-8'
-fi
-
-#
-# Paths
-#
-
-typeset -gU cdpath fpath mailpath path
-
-# Set the the list of directories that cd searches.
-# cdpath=(
-#   $cdpath
-# )
-
-# Set the list of directories that Zsh searches for programs.
-path=(
-  /usr/local/{bin,sbin}
-  $path
-)
-
-#
-# Less
-#
-
-# Set the default Less options.
-# Mouse-wheel scrolling has been disabled by -X (disable screen clearing).
-# Remove -X and -F (exit if the content fits on one screen) to enable it.
-export LESS='-F -g -i -M -R -S -w -X -z-4'
-
-# Set the Less input preprocessor.
-if (( $+commands[lesspipe.sh] )); then
-  export LESSOPEN='| /usr/bin/env lesspipe.sh %s 2>&-'
-fi
-
-#
-# Temporary Files
-#
-
-if [[ ! -d "$TMPDIR" ]]; then
-  export TMPDIR="/tmp/$USER"
-  mkdir -p -m 700 "$TMPDIR"
-fi
-
-TMPPREFIX="${TMPDIR%/}/zsh"
-if [[ ! -d "$TMPPREFIX" ]]; then
-  mkdir -p "$TMPPREFIX"
+# Ensure that a non-login, non-interactive shell has a defined environment.
+if [[ "$SHLVL" -eq 1 && ! -o LOGIN ]]; then
+  source "${ZDOTDIR:-$HOME}/.zprofile"
 fi