fix: zsh impl of realpath handles old macOS BSD realpath

doc/zsdoc/zinit-install.zsh.adoc

@@ -24,6 +24,7 @@ Documentation automatically generated with `zshelldoc'
  .zinit-json-get-value
  .zinit-json-to-array
  .zinit-mirror-using-svn
+ .zinit-realpath
  .zinit-setup-plugin-dir
  .zinit-single-line
  .zinit-update-snippet
@@ -192,7 +193,7 @@ ____
 
 ____
 
-Has 377 line(s). Calls functions:
+Has 380 line(s). Calls functions:
 
  .zinit-download-snippet
  |-- .zinit-download-file-stdout
@@ -210,10 +211,9 @@ Has 377 line(s). Calls functions:
  |   `-- zinit.zsh/.zinit-any-to-user-plugin
  |-- .zinit-mirror-using-svn
  |-- zinit-side.zsh/.zinit-store-ices
- |-- zinit.zsh/+zi-log
- `-- zinit.zsh/is-at-least
+ `-- zinit.zsh/+zi-log
 
-Uses feature(s): _is-at-least_, _setopt_, _trap_, _zcompile_
+Uses feature(s): _setopt_, _trap_, _zcompile_
 
 Called by:
 
@@ -456,6 +456,20 @@ Called by:
 
  .zinit-download-snippet
 
+==== .zinit-realpath
+
+____
+
+
+ $1: Initial path
+ $2: Target path
+
+____
+
+Has 16 line(s). Doesn't call other functions.
+
+Not called by script or any function (may be e.g. a hook, a Zle widget, etc.).
+
 ==== .zinit-setup-plugin-dir
 
 ____
@@ -539,8 +553,7 @@ Has 76 line(s). Calls functions:
  |   |   `-- zinit.zsh/.zinit-any-to-user-plugin
  |   |-- .zinit-mirror-using-svn
  |   |-- zinit-side.zsh/.zinit-store-ices
- |   |-- zinit.zsh/+zi-log
- |   `-- zinit.zsh/is-at-least
+ |   `-- zinit.zsh/+zi-log
  |-- zinit.zsh/+zi-log
  |-- zinit.zsh/.zinit-get-object-path
  `-- zinit.zsh/.zinit-pack-ice

doc/zsdoc/zinit.zsh.adoc

@@ -1965,5 +1965,4 @@ Called by:
  :zinit-tmp-subst-autoload
  :zinit-tmp-subst-bindkey
  Script-Body
- zinit-install.zsh/.zinit-download-snippet
 

tests/commands.zunit

@@ -63,6 +63,7 @@
   assert $output contains 'Already up-to-date.'
   assert $state equals 0
 }
+
 @test 'set-debug' {
   ZINIT+=(DEBUG 'true')
   run +zi-log -n '{dbg} message'
@@ -73,3 +74,5 @@
   run +zi-log -n '{m} message'
   assert $output contains 'message'; assert $state equals 0
 }
+
+# vim:ft=zsh:sw=2:sts=2:et:foldmarker={,}:foldmethod=marker

zinit-install.zsh

@@ -6,7 +6,28 @@ builtin source "${ZINIT[BIN_DIR]}/zinit-side.zsh" || {
     builtin print -P "${ZINIT[col-error]}ERROR:%f%b Couldn't find ${ZINIT[col-obj]}zinit-side.zsh%f%b."
     return 1
 }
-
+# FUNCTION: .zinit-realpath [[[
+#
+# $1: Initial path
+# $2: Target path
+.zinit-realpath () {
+    [[ $# -ge 1 ]] && [[ $# -le 2 ]] || return 1
+    local target=${${2:-$1}:a} current=${${${2:+$1}:-$PWD}:a} relative=''
+    local appendix="${target#/}"
+    while appendix="${target#${current}/}"
+        [[ $current != '/' ]] && [[ $appendix = $target ]]
+    do
+        if [[ $current = $appendix ]]; then
+            relative="${relative:-.}"
+            builtin print -- "${relative#/}"
+            return 0
+        fi
+        current=${current%/*}
+        relative="$relative${relative:+/}.."
+    done
+    relative+=${relative:+${appendix:+/}}${appendix#/}
+    builtin print -- "$relative"
+} # ]]]
 # FUNCTION: .zinit-jq-check [[[
 # Check if jq is available and outputs an error message with instructions if
 # that's not the case
@@ -1193,34 +1214,37 @@ builtin source "${ZINIT[BIN_DIR]}/zinit-side.zsh" || {
                     "accessible (wrong permissions).{rst}"
                 retval=4
             }
-            if ! (( ${+ICE[link]} )) {
-                if (( !OPTS[opt_-q,--quiet] )) && [[ $url != /dev/null ]] {
+
+            if ! (( ${+ICE[link]} )); then
+                if (( !OPTS[opt_-q,--quiet] )) && [[ $url != /dev/null ]]; then
                     +zi-log "{msg}Copying {file}$filename{msg}{…}{rst}"
-                    command cp -vf "$url" "$local_dir/$dirname/$filename" || \
-                        { +zi-log "{ehi}ERROR:{error} The file copying has been unsuccessful.{rst}"; retval=4; }
-                } else {
-                    command cp -f "$url" "$local_dir/$dirname/$filename" &>/dev/null || \
-                        { +zi-log "{ehi}ERROR:{error} The copying of {file}$filename{error} has been unsuccessful"\
-    "${${(M)OPTS[opt_-q,--quiet]:#1}:+, skip the -q/--quiet option for more information}.{rst}"; retval=4; }
-                }
-            } else {
-                if (( $+commands[realpath] )) {
-                    local rpv="$(realpath --version | head -n1 | sed -E 's/realpath (\(.*\))?//g')"
-                    if is-at-least 8.23 $rpv; then
-                        rel_url="$(realpath --relative-to="$local_dir/$dirname" "$url")" && \
-                            { url="$rel_url" }
-                    fi
-                }
-                if (( !OPTS[opt_-q,--quiet] )) && [[ $url != /dev/null ]] {
+                    command cp -vf "$url" "$local_dir/$dirname/$filename" || {
+                        +zi-log "{ehi}ERROR:{error} The file copying has been unsuccessful.{rst}"
+                        retval=4
+                    }
+                else
+                    command cp -f "$url" "$local_dir/$dirname/$filename" &> /dev/null || {
+                        +zi-log "{ehi}ERROR:{error} The copying of {file}$filename{error} has been unsuccessful" "${${(M)OPTS[opt_-q,--quiet]:#1}:+, skip the -q/--quiet option for more information}.{rst}"
+                        retval=4
+                    }
+                fi
+            else
+                rel_url="$(.zinit-realpath "$local_dir/$dirname" "$url")"
+                url="${rel_url}"
+                if (( !OPTS[opt_-q,--quiet] )) && [[ $url != /dev/null ]]; then
                     +zi-log "{msg}Linking {file}$filename{msg}{…}{rst}"
-                    command ln -svf "$url" "$local_dir/$dirname/$filename" || \
-                        { +zi-log "{ehi}ERROR:{error} The file linking has been unsuccessful.{rst}"; retval=4; }
-                } else {
-                    command ln -sf "$url" "$local_dir/$dirname/$filename" &>/dev/null || \
-                        { +zi-log "{ehi}ERROR:{error} The link of {file}$filename{error} has been unsuccessful"\
-    "${${(M)OPTS[opt_-q,--quiet]:#1}:+, skip the -q/--quiet option for more information}.{rst}"; retval=4; }
-                }
-            }
+                    command ln -svf "$url" "$local_dir/$dirname/$filename" || {
+                        +zi-log "{ehi}ERROR:{error} The file linking has been unsuccessful.{rst}"
+                        retval=4
+                    }
+                else
+                    command ln -sf "$url" "$local_dir/$dirname/$filename" &> /dev/null || {
+                        +zi-log "{ehi}ERROR:{error} The link of {file}$filename{error} has been unsuccessful" "${${(M)OPTS[opt_-q,--quiet]:#1}:+, skip the -q/--quiet option for more information}.{rst}"
+                        retval=4
+                    }
+                fi
+            fi
+
         }
 
         (( retval == 4 )) && { command rmdir "$local_dir/$dirname" 2>/dev/null; return $retval; }