Added truncatePath to utilities.zsh

Added `function truncatePath()` to utilities.zsh to take care of
truncation. This is pure zsh code, without calls to `sed`. Parameters
are:
   * $1 Path: string - the directory path to be truncated
   * $2 Length: integer - length to truncate to
   * $3 Delimiter: string - the delimiter to use
   * $4 From: string - "right" | "middle". If omited, assumes right.

Cleaned up code to use the new function instead.

1 files changed, 75 insertions, 0 deletions

diff --git a/functions/utilities.zsh b/functions/utilities.zsh
index b4bfb838..9f1ea53e 100644
--- a/functions/utilities.zsh
+++ b/functions/utilities.zsh
@@ -213,6 +213,81 @@ function segmentShouldBeJoined() {
   fi
 }
 
+################################################################
+# Given a directory path, truncate it according to the settings.
+# Parameters:
+#   * $1 Path: string - the directory path to be truncated
+#   * $2 Length: integer - length to truncate to
+#   * $3 Delimiter: string - the delimiter to use
+#   * $4 From: string - "right" | "middle". If omited, assumes right.
+function truncatePath() {
+  # if the current path is not 1 character long (e.g. "/" or "~")
+  if (( ${#1} > 1 )); then
+    # convert $2 from string to integer
+    2=$(( $2 ))
+    # set $3 to "" if not defined
+    [[ -z $3 ]] && local 3="" || 3=$(echo -n $3)
+    # set $4 to "right" if not defined
+    [[ -z $4 ]] && 4="right"
+    # create a variable for the truncated path.
+    local trunc_path
+    # if the path is in the home folder, don't add a "/" to the start
+    [[ $1 != "~"* ]] && trunc_path='/' || trunc_path=''
+    # split the path into an array using "/" as the delimiter and remove "~/"
+    local paths=(${(s:/:)1})
+    # declare locals for the directory being tested and its length
+    local test_dir test_dir_length
+    # do the needed truncation
+    case $4 in
+      right)
+        # include the delimiter length in the threshhold
+        local threshhold=$(( $2 + ${#3} ))
+        # loop through the paths
+        for (( i=1; i<${#paths}; i++ )); do
+          # get the current directory value
+          test_dir=$paths[$i]
+          test_dir_length=${#test_dir}
+          # only truncate if the resulting truncation will be shorter than
+          # the truncation + delimiter length and at least 3 characters
+          if (( $test_dir_length > $threshhold )) && (( $test_dir_length > 3 )); then
+            # use the first $2 characters and the delimiter
+            trunc_path+="${test_dir:0:$2}$3/"
+          else
+            # use the full path
+            trunc_path+="${test_dir}/"
+          fi
+        done
+      ;;
+      middle)
+        # we need double the length for start and end truncation + delimiter length
+        local threshhold=$(( $2 * 2 + ${#3} ))
+        # create a variable for the start of the end truncation
+        local last_pos
+        # loop through the paths
+        for (( i=1; i<${#paths}; i++ )); do
+          # get the current directory value
+          test_dir=$paths[$i]
+          test_dir_length=${#test_dir}
+          # only truncate if the resulting truncation will be shorter than
+          # the truncation + delimiter length
+          if (( $test_dir_length > $threshhold + ${#3} )); then
+            # use the first $2 characters, the delimiter and the last $2 characters
+            last_pos=$(( $test_dir_length - $2 ))
+            trunc_path+="${test_dir:0:$2}$3${test_dir:$last_pos:$test_dir_length}/"
+          else
+            # use the full path
+            trunc_path+="${test_dir}/"
+          fi
+        done
+      ;;
+    esac
+    # return the truncated path + the current directory
+    echo $trunc_path${1:t}
+  else # current path is 1 character long (e.g. "/" or "~")
+    echo $1
+  fi
+}
+
 # Given a directory path, truncate it according to the settings for
 # `truncate_from_right`
 function truncatePathFromRight() {