From a8df5d587cb8da3537bd0ecbb11ac6016828c75d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Mislav=20Marohni=C4=87?= <mislav.marohnic@gmail.com>
Date: Wed, 15 Oct 2014 03:39:04 +0200
Subject: [PATCH 1/3] Avoid changing directories during rehash process

---
 libexec/rbenv-rehash | 29 +++++++++++------------------
 1 file changed, 11 insertions(+), 18 deletions(-)

diff --git a/libexec/rbenv-rehash b/libexec/rbenv-rehash
index 5ec195ec..d89af7fa 100755
--- a/libexec/rbenv-rehash
+++ b/libexec/rbenv-rehash
@@ -70,9 +70,10 @@ SH
 # of the first shim in the shims directory, assume rbenv has been
 # upgraded and the existing shims need to be removed.
 remove_outdated_shims() {
-  for shim in *; do
+  local shim
+  for shim in "$SHIM_PATH"/*; do
     if ! diff "$PROTOTYPE_SHIM_PATH" "$shim" >/dev/null 2>&1; then
-      for shim in *; do rm -f "$shim"; done
+      rm -f "$SHIM_PATH"/*
     fi
     break
   done
@@ -82,10 +83,9 @@ remove_outdated_shims() {
 # registered for installation as a shim. In this way, plugins may call
 # `make_shims` with a glob to register many shims at once.
 make_shims() {
-  local shims=("$@")
-
-  for file in "${shims[@]}"; do
-    local shim="${file##*/}"
+  local file shim
+  for file; do
+    shim="${file##*/}"
     register_shim "$shim"
   done
 }
@@ -110,9 +110,10 @@ register_shim() {
 # `registered_shims` array and create a link if one does not already
 # exist.
 install_registered_shims() {
-  local shim
+  local shim file
   for shim in "${registered_shims[@]}"; do
-    [ -e "$shim" ] || ln -f "$PROTOTYPE_SHIM_PATH" "$shim"
+    file="${SHIM_PATH}/${shim}"
+    [ -e "$file" ] || ln -f "$PROTOTYPE_SHIM_PATH" "$file"
   done
 }
 
@@ -122,16 +123,13 @@ install_registered_shims() {
 # removed.
 remove_stale_shims() {
   local shim
-  for shim in *; do
-    if [[ "$registered_shims_index" != *"/$shim/"* ]]; then
+  for shim in "$SHIM_PATH"/*; do
+    if [[ "$registered_shims_index" != *"/${shim##*/}/"* ]]; then
       rm -f "$shim"
     fi
   done
 }
 
-
-# Change to the shims directory.
-cd "$SHIM_PATH"
 shopt -s nullglob
 
 # Create the prototype shim, then register shims for all known
@@ -140,8 +138,6 @@ create_prototype_shim
 remove_outdated_shims
 make_shims ../versions/*/bin/*
 
-# Restore the previous working directory.
-cd "$OLDPWD"
 
 # Allow plugins to register shims.
 OLDIFS="$IFS"
@@ -152,8 +148,5 @@ for script in "${scripts[@]}"; do
   source "$script"
 done
 
-# Change back to the shims directory to install the registered shims
-# and remove stale shims.
-cd "$SHIM_PATH"
 install_registered_shims
 remove_stale_shims

From 89d4e8a0e0e16a4afd7c834d28d1ba21b81a8182 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Mislav=20Marohni=C4=87?= <mislav.marohnic@gmail.com>
Date: Wed, 15 Oct 2014 04:05:41 +0200
Subject: [PATCH 2/3] Speed up rehash process when there are many Ruby versions

On my system that has 25 versions under rbenv, this speeds up rehash
almost 3-fold:

- before: 391 ms
- after:  134 ms

This is achieved by removing duplicate names of executables before
registering them as shims. Since most Rubies will share a lot of the
same executable names ("ruby", "rake", "bundle", ...), this is a
considerable reduction in number of shims registered.
---
 libexec/rbenv-rehash | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/libexec/rbenv-rehash b/libexec/rbenv-rehash
index d89af7fa..df221e65 100755
--- a/libexec/rbenv-rehash
+++ b/libexec/rbenv-rehash
@@ -79,6 +79,14 @@ remove_outdated_shims() {
   done
 }
 
+# List basenames of executables for every Ruby version
+list_executable_names() {
+  local file
+  for file in "$RBENV_ROOT"/versions/*/bin/*; do
+    echo "${file##*/}"
+  done
+}
+
 # The basename of each argument passed to `make_shims` will be
 # registered for installation as a shim. In this way, plugins may call
 # `make_shims` with a glob to register many shims at once.
@@ -136,7 +144,7 @@ shopt -s nullglob
 # executables.
 create_prototype_shim
 remove_outdated_shims
-make_shims ../versions/*/bin/*
+make_shims $(list_executable_names | sort -u)
 
 
 # Allow plugins to register shims.

From 1381c2ca79dc515406f82cbac380706ad9c9ec55 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Mislav=20Marohni=C4=87?= <mislav.marohnic@gmail.com>
Date: Wed, 15 Oct 2014 05:12:28 +0200
Subject: [PATCH 3/3] Simplify the shims registration implementation in
 `rbenv-rehash`

It doesn't need to be a bash array and we don't need a separate index of
shims registered. Simply keep everything in a space-separated string and
use that as an index as well.

This assumes that executable names *never* have spaces in them.
---
 libexec/rbenv-rehash | 23 ++++++-----------------
 test/rehash.bats     | 21 ++++++++++++++++++++-
 2 files changed, 26 insertions(+), 18 deletions(-)

diff --git a/libexec/rbenv-rehash b/libexec/rbenv-rehash
index df221e65..19f9daa5 100755
--- a/libexec/rbenv-rehash
+++ b/libexec/rbenv-rehash
@@ -98,28 +98,17 @@ make_shims() {
   done
 }
 
-# Create an empty array for the list of registered shims and an empty
-# string to use as a search index.
-registered_shims=()
-registered_shims_index=""
+registered_shims=" "
 
-# We will keep track of shims registered for installation with the
-# global `registered_shims` array and with a global search index
-# string. The array will let us iterate over all registered shims. The
-# index string will let us quickly check whether a shim with the given
-# name has been registered or not.
+# Registers the name of a shim to be generated.
 register_shim() {
-  local shim="$@"
-  registered_shims["${#registered_shims[@]}"]="$shim"
-  registered_shims_index="$registered_shims_index/$shim/"
+  registered_shims="${registered_shims}${1} "
 }
 
-# To install all the registered shims, we iterate over the
-# `registered_shims` array and create a link if one does not already
-# exist.
+# Install all the shims registered via `make_shims` or `register_shim` directly.
 install_registered_shims() {
   local shim file
-  for shim in "${registered_shims[@]}"; do
+  for shim in $registered_shims; do
     file="${SHIM_PATH}/${shim}"
     [ -e "$file" ] || ln -f "$PROTOTYPE_SHIM_PATH" "$file"
   done
@@ -132,7 +121,7 @@ install_registered_shims() {
 remove_stale_shims() {
   local shim
   for shim in "$SHIM_PATH"/*; do
-    if [[ "$registered_shims_index" != *"/${shim##*/}/"* ]]; then
+    if [[ "$registered_shims" != *" ${shim##*/} "* ]]; then
       rm -f "$shim"
     fi
   done
diff --git a/test/rehash.bats b/test/rehash.bats
index ba12a245..74f55a97 100755
--- a/test/rehash.bats
+++ b/test/rehash.bats
@@ -53,7 +53,7 @@ ruby
 OUT
 }
 
-@test "removes stale shims" {
+@test "removes outdated shims" {
   mkdir -p "${RBENV_ROOT}/shims"
   touch "${RBENV_ROOT}/shims/oldshim1"
   chmod +x "${RBENV_ROOT}/shims/oldshim1"
@@ -67,6 +67,25 @@ OUT
   assert [ ! -e "${RBENV_ROOT}/shims/oldshim1" ]
 }
 
+@test "do exact matches when removing stale shims" {
+  create_executable "2.0" "unicorn_rails"
+  create_executable "2.0" "rspec-core"
+
+  rbenv-rehash
+
+  cp "$RBENV_ROOT"/shims/{rspec-core,rspec}
+  cp "$RBENV_ROOT"/shims/{rspec-core,rails}
+  cp "$RBENV_ROOT"/shims/{rspec-core,uni}
+  chmod +x "$RBENV_ROOT"/shims/{rspec,rails,uni}
+
+  run rbenv-rehash
+  assert_success ""
+
+  assert [ ! -e "${RBENV_ROOT}/shims/rails" ]
+  assert [ ! -e "${RBENV_ROOT}/shims/rake" ]
+  assert [ ! -e "${RBENV_ROOT}/shims/uni" ]
+}
+
 @test "binary install locations containing spaces" {
   create_executable "dirname1 p247" "ruby"
   create_executable "dirname2 preview1" "rspec"