handle missing configuration file

.gitignore

@@ -0,0 +1 @@
+goto.yaml

goto.bash

@@ -9,17 +9,25 @@ readonly __GOTO_FILE=${__GOTO_ROOT_DIR}/goto.yaml
 # path to yq executable
 readonly __GOTO_YQ=/usr/local/bin/yq
 
+__goto_exists() {
+  [[ -f ${__GOTO_FILE} ]]
+}
+
 __goto_load() {
   # load the directory mappings from the configuration file into the variable reference passed as parameter
   # $1: name of the result associative array to create
 
   local -n data_ref=$1
+  data_ref=()
+
+  if ! __goto_exists; then
+    return
+  fi
+
   local entries entry key value
 
   mapfile entries < <(${__GOTO_YQ} 'explode(.) | to_entries[] | "\(.key) \(.value)"' ${__GOTO_FILE})
 
-  data_ref=()
-
   for entry in "${entries[@]}"; do
     if [[ -z "${entry}" ]]; then
       continue
@@ -146,7 +154,11 @@ __goto_add() {
     dir_path="${PWD}"
   fi
 
+  if __goto_exists; then
     dir_alias="${dir_alias}" dir_path="${dir_path}"  ${__GOTO_YQ} -i '. | (.[env(dir_alias)] = env(dir_path))' ${__GOTO_FILE}
+  else
+    dir_alias="${dir_alias}" dir_path="${dir_path}"  ${__GOTO_YQ} '.[env(dir_alias)] = env(dir_path)' ${__GOTO_FILE}
+  fi
 }
 
 __goto_remove() {
@@ -154,6 +166,10 @@ __goto_remove() {
   # command: goto -r <directory alias>
   # $1: directory alias
 
+  if ! __goto_exists; then
+    return
+  fi
+
   dir_alias="$1" ${__GOTO_YQ} -i 'del(.[env(dir_alias)])' ${__GOTO_FILE}
 }
 
@@ -162,13 +178,17 @@ __goto_get() {
   # command: goto -g <directory alias>
   # $1: directory alias
 
+  if ! __goto_exists; then
+    return 11
+  fi
+
   local dir_path="$(dir_alias="$1" ${__GOTO_YQ} '.[env(dir_alias)] // ""' ${__GOTO_FILE})"
 
-  if [[ -n "${dir_path}" ]]; then
-    __goto_resolve_path "${dir_path}"
-  else
-    return 10;
+  if [[ -z "${dir_path}" ]]; then
+    return 10
   fi
+  
+  __goto_resolve_path "${dir_path}"
 }
 
 goto() {
@@ -221,6 +241,11 @@ goto() {
     return
   fi
 
+  if ! __goto_exists; then
+    echo "goto: $1: configuration file not found" >&2
+    return 3
+  fi
+
   local dir_path="$(dir_alias="$1" ${__GOTO_YQ} '.[env(dir_alias)] // ""' ${__GOTO_FILE})"
 
   if [[ -z "${dir_path}" ]]; then