From 1c3f8da6c38bdfecf3dbf01c6753a6fd27032b9d Mon Sep 17 00:00:00 2001
From: Jordan Harband <ljharb@gmail.com>
Date: Wed, 27 Apr 2016 14:23:34 -0700
Subject: [PATCH] `nvm alias`: factor out alias creation to `nvm_make_alias`

---
 nvm.sh                              | 24 ++++++++++++++++++++----
 test/fast/Unit tests/nvm_make_alias | 19 +++++++++++++++++++
 2 files changed, 39 insertions(+), 4 deletions(-)
 create mode 100755 test/fast/Unit tests/nvm_make_alias

diff --git a/nvm.sh b/nvm.sh
index a42334e..6135a1f 100755
--- a/nvm.sh
+++ b/nvm.sh
@@ -464,6 +464,22 @@ nvm_print_default_alias() {
   fi
 }
 
+nvm_make_alias() {
+  local ALIAS
+  ALIAS="${1-}"
+  if [ -z "$ALIAS" ]; then
+    >&2 echo "an alias name is required"
+    return 1
+  fi
+  local VERSION
+  VERSION="${2-}"
+  if [ -z "$VERSION" ]; then
+    >&2 echo "an alias target version is required"
+    return 2
+  fi
+  echo "$VERSION" | tee "$(nvm_alias_path)/${ALIAS}" >/dev/null
+}
+
 nvm_alias() {
   local ALIAS
   ALIAS="${1-}"
@@ -2356,11 +2372,11 @@ $NVM_LS_REMOTE_POST_MERGED_OUTPUT" | command grep -v "N/A" | command sed '/^$/d'
       if [ $? -ne 0 ]; then
         echo "! WARNING: Version '${3-}' does not exist." >&2
       fi
-      echo "$3" | tee "$NVM_ALIAS_DIR/${2-}" >/dev/null
-      if [ ! "_$3" = "_$VERSION" ]; then
-        echo "${2-} -> ${3-} (-> $VERSION)"
-      else
+      nvm_make_alias "${2-}" "${3-}"
+      if [ "_$3" = "_$VERSION" ]; then
         echo "${2-} -> ${3-}"
+      else
+        echo "${2-} -> ${3-} (-> $VERSION)"
       fi
     ;;
     "unalias" )
diff --git a/test/fast/Unit tests/nvm_make_alias b/test/fast/Unit tests/nvm_make_alias
new file mode 100755
index 0000000..c57906d
--- /dev/null
+++ b/test/fast/Unit tests/nvm_make_alias	
@@ -0,0 +1,19 @@
+#!/bin/sh
+
+die () { echo $@ ; exit 1; }
+
+. ../../../nvm.sh
+
+OUTPUT="$(nvm_make_alias 2>&1)"
+EXIT_CODE="$(nvm_make_alias >/dev/null 2>&1 ; echo $?)"
+EXPECTED_OUTPUT='an alias name is required'
+
+[ "_$OUTPUT" = "_$EXPECTED_OUTPUT" ] || die "\`nvm_make_alias\` did not error with '$EXPECTED_OUTPUT'; got '$OUTPUT'"
+[ "$EXIT_CODE" -eq 1 ] || die "\`nvm_make_alias\` did not exit with 1, got '$EXIT_CODE'"
+
+OUTPUT="$(nvm_make_alias foo 2>&1)"
+EXIT_CODE="$(nvm_make_alias foo >/dev/null 2>&1 ; echo $?)"
+EXPECTED_OUTPUT='an alias target version is required'
+
+[ "_$OUTPUT" = "_$EXPECTED_OUTPUT" ] || die "\`nvm_make_alias foo\` did not error with '$EXPECTED_OUTPUT'; got '$OUTPUT'"
+[ "$EXIT_CODE" -eq 2 ] || die "\`nvm_make_alias foo\` did not exit with 2, got '$EXIT_CODE'"