Merge pull request #372 from sstephenson/exec-next

Change `exec` semantics to allow using rbenv from a ruby process

test/exec.bats

@@ -3,15 +3,37 @@
 load test_helper
 
 create_executable() {
-  name="${1?}"
+  local file="${1?}"
+  [[ $file == */* ]] || file="${RBENV_ROOT}/versions/${RBENV_VERSION}/bin/$file"
   shift 1
-  bin="${RBENV_ROOT}/versions/${RBENV_VERSION}/bin"
-  mkdir -p "$bin"
+  mkdir -p "${file%/*}"
   { if [ $# -eq 0 ]; then cat -
     else echo "$@"
     fi
-  } | sed -Ee '1s/^ +//' > "${bin}/$name"
-  chmod +x "${bin}/$name"
+  } | sed -Ee '1s/^[[:space:]]+//' > "$file"
+  chmod +x "$file"
+}
+
+# Fake ruby executable that emulates `ruby -S <cmd>' behavior by running the
+# first `cmd' found in RUBYPATH/PATH as bash script.
+create_ruby_executable() {
+  create_executable "${1:-ruby}" <<SH
+#!$BASH
+if [[ \$1 == "-S"* ]]; then
+  cmd="\${1#-S}"
+  [ -n "\$cmd" ] || cmd="\$2"
+  found="\$(PATH="\${RUBYPATH:-\$PATH}" \$(command -v which) \$cmd)"
+  # assert that the found executable has ruby for shebang
+  if head -1 "\$found" | grep ruby >/dev/null; then
+    \$BASH "\$found"
+  else
+    echo "ruby: no Ruby script found in input (LoadError)" >&2
+    exit 1
+  fi
+else
+  echo 'ruby (rbenv test)'
+fi
+SH
 }
 
 @test "fails with invalid version" {
@@ -82,26 +104,56 @@ ${RBENV_ROOT}/versions/2.0/bin/ruby
 OUT
 }
 
+@test "doesn't mutate PATH" {
+  export RBENV_VERSION="2.0"
+  create_executable "ruby" <<SH
+#!$BASH
+echo \$PATH
+SH
+
+  run rbenv-exec ruby
+  assert_success "$PATH"
+}
+
+@test "doesn't set RUBYPATH" {
+  export RBENV_VERSION="2.0"
+  create_executable "ruby" <<SH
+#!$BASH
+echo \$RUBYPATH
+SH
+
+  RUBYPATH="" run rbenv-exec ruby
+  assert_success
+  assert_output ""
+}
+
+@test "allows subprocesses to select a different RBENV_VERSION" {
+  RBENV_VERSION=1.8 create_executable "rake" <<SH
+#!$BASH
+echo rake 1.8
+SH
+
+  export RBENV_VERSION="2.0"
+  create_executable "rake" "#!/bin/sh"
+  create_executable "ruby" <<SH
+#!$BASH
+echo ruby 2.0
+RBENV_VERSION=1.8 exec rake
+SH
+
+  rbenv rehash
+  run ruby
+  assert_success
+  assert_output <<OUT
+ruby 2.0
+rake 1.8
+OUT
+}
+
 @test "supports ruby -S <cmd>" {
   export RBENV_VERSION="2.0"
 
-  # emulate `ruby -S' behavior
-  create_executable "ruby" <<SH
-#!$BASH
-if [[ \$1 == "-S"* ]]; then
-  found="\$(PATH="\${RUBYPATH:-\$PATH}" which \$2)"
-  # assert that the found executable has ruby for shebang
-  if head -1 "\$found" | grep ruby >/dev/null; then
-    \$BASH "\$found"
-  else
-    echo "ruby: no Ruby script found in input (LoadError)" >&2
-    exit 1
-  fi
-else
-  echo 'ruby 2.0 (rbenv test)'
-fi
-SH
-
+  create_ruby_executable
   create_executable "rake" <<SH
 #!/usr/bin/env ruby
 echo hello rake
@@ -111,3 +163,151 @@ SH
   run ruby -S rake
   assert_success "hello rake"
 }
+
+@test "supports ruby -S with system version" {
+  export RBENV_VERSION=2.0
+  create_executable "ruby" "#!/bin/sh"
+  create_executable "rake" "#!/bin/sh"
+  rbenv-rehash
+
+  create_ruby_executable "${RBENV_TEST_DIR}/bin/ruby"
+  create_executable "${RBENV_TEST_DIR}/bin/rake" <<SH
+#!/usr/bin/env ruby
+echo system rake
+SH
+
+  RBENV_VERSION=system run ruby -S rake
+  assert_success "system rake"
+}
+
+@test "ruby -S allows commands higher in PATH to have precedence over shims" {
+  export RBENV_VERSION="2.0"
+
+  create_ruby_executable
+  create_executable "rake" <<SH
+#!/usr/bin/env ruby
+echo normal rake
+SH
+  rbenv-rehash
+
+  create_executable "${HOME}/bin/rake" <<SH
+#!/usr/bin/env ruby
+echo override rake
+SH
+
+  PATH="${HOME}/bin:$PATH" run ruby -S rake
+  assert_success "override rake"
+}
+
+@test "ruby -S respects existing RUBYPATH" {
+  export RBENV_VERSION="2.0"
+
+  create_ruby_executable
+  create_executable "rspec" <<SH
+#!/usr/bin/env ruby
+echo normal rspec
+SH
+  rbenv-rehash
+
+  create_executable "${HOME}/bin/rspec" "#!/bin/sh"
+  create_executable "${HOME}/bin/rake" <<SH
+#!/usr/bin/env ruby
+echo override rake
+SH
+
+  export RUBYPATH="${HOME}/bin"
+  run ruby -S rspec
+  assert_success "normal rspec"
+  run ruby -S rake
+  assert_success "override rake"
+}
+
+@test "supports nested ruby -S invocations to change RBENV_VERSION" {
+  export RBENV_VERSION="1.8"
+  create_ruby_executable
+  create_executable "rspec" <<SH
+#!/usr/bin/env ruby
+echo rspec 1.8
+SH
+
+  export RBENV_VERSION="2.0"
+  create_ruby_executable
+  create_executable "rspec" <<SH
+#!/usr/bin/env ruby
+echo rspec 2.0
+SH
+  create_executable "rake" <<SH
+#!/usr/bin/env ruby
+echo rake 2.0
+RBENV_VERSION=1.8 ruby -S rspec
+SH
+
+  rbenv-rehash
+  run ruby -S rake
+  assert_success
+  assert_output <<OUT
+rake 2.0
+rspec 1.8
+OUT
+}
+
+@test "supports system ruby -S invocation to select a different RBENV_VERSION" {
+  export RBENV_VERSION="2.0"
+  create_ruby_executable
+  create_executable "rspec" <<SH
+#!/usr/bin/env ruby
+echo rspec 2.0
+SH
+  rbenv-rehash
+
+  create_ruby_executable "${RBENV_TEST_DIR}/bin/ruby"
+  create_executable "${RBENV_TEST_DIR}/bin/rspec" <<SH
+#!/usr/bin/env ruby
+echo system rspec
+SH
+  create_executable "${RBENV_TEST_DIR}/bin/rake" <<SH
+#!/usr/bin/env ruby
+echo system rake
+RBENV_VERSION=2.0 ruby -S rspec
+SH
+
+  RBENV_VERSION=system run ruby -S rake
+  assert_success
+  assert_output <<OUT
+system rake
+rspec 2.0
+OUT
+}
+
+@test "nested ruby -S invocations preserve PATH precedence" {
+  export RBENV_VERSION="2.0"
+  create_ruby_executable
+  create_executable "rspec" <<SH
+#!/usr/bin/env ruby
+echo rspec 2.0
+SH
+  rbenv-rehash
+
+  create_ruby_executable "${RBENV_TEST_DIR}/bin/ruby"
+  create_executable "${RBENV_TEST_DIR}/bin/rspec" <<SH
+#!/usr/bin/env ruby
+echo system rspec
+SH
+  create_executable "${RBENV_TEST_DIR}/bin/rake" <<SH
+#!/usr/bin/env ruby
+echo system rake
+RBENV_VERSION=2.0 ruby -S rspec
+SH
+
+  create_executable "${HOME}/bin/rspec" <<SH
+#!/usr/bin/env ruby
+echo override rspec
+SH
+
+  PATH="${HOME}/bin:$PATH" RBENV_VERSION=system run ruby -S rake
+  assert_success
+  assert_output <<OUT
+system rake
+override rspec
+OUT
+}