completion/pip: simplify code flow

Short-circuit the loader rather than indenting nearly the whole file.

ALSÖ, assign the `_pip_completion()` handler directly once it's loaded so that we get out of the way once we load it.

completion/available/pip.completion.bash

@@ -6,14 +6,15 @@
 # If the pip package is installed within virtual environments, say, python managed by pyenv,
 # you should first initialize the corresponding environment.
 # So that pip is in the system's path.
-if _command_exists pip; then
-	function __bash_it_complete_pip() {
-		if _command_exists _pip_completion; then
-			_pip_completion "$@"
-		else
-			eval "$(pip completion --bash)"
-			_pip_completion "$@"
-		fi
-	}
-	complete -o default -F __bash_it_complete_pip pip
-fi
+_command_exists pip || return
+
+function __bash_it_complete_pip() {
+	if _command_exists _pip_completion; then
+		complete -o default -F _pip_completion pip
+		_pip_completion "$@"
+	else
+		eval "$(pip completion --bash)"
+		_pip_completion "$@"
+	fi
+}
+complete -o default -F __bash_it_complete_pip pip

completion/available/pip3.completion.bash

@@ -6,14 +6,15 @@
 # If the pip package is installed within virtual environments, say, python managed by pyenv,
 # you should first initialize the corresponding environment.
 # So that pip3 is in the system's path.
-if _command_exists pip3; then
-	function __bash_it_complete_pip3() {
-		if _command_exists _pip_completion; then
-			_pip_completion "$@"
-		else
-			eval "$(pip3 completion --bash)"
-			_pip_completion "$@"
-		fi
-	}
-	complete -o default -F __bash_it_complete_pip3 pip3
-fi
+_command_exists pip3 || return
+
+function __bash_it_complete_pip3() {
+	if _command_exists _pip_completion; then
+		complete -o default -F _pip_completion pip3
+		_pip_completion "$@"
+	else
+		eval "$(pip3 completion --bash)"
+		_pip_completion "$@"
+	fi
+}
+complete -o default -F __bash_it_complete_pip3 pip3