ESLint won’t convert these automatically because it can’t rule out a
behavior difference arising from an access to a self-referential var
before it’s initialized:
> var x = (f => f())(() => x);
undefined
> let y = (f => f())(() => y);
Thrown:
ReferenceError: Cannot access 'y' before initialization
at repl:1:26
at repl:1:15
Signed-off-by: Anders Kaseorg <anders@zulipchat.com>
With webpack, variables declared in each file are already file-local
(Global variables need to be explicitly exported), so these IIFEs are
no longer needed.
Signed-off-by: Anders Kaseorg <andersk@mit.edu>
This commit prepares the frontend code to be consumed by webpack.
It is a hack: In theory, modules should be declaring and importing the
modules they depend on and the globals they expose directly.
However, that requires significant per-module work, which we don't
really want to block moving our toolchain to webpack on.
So we expose the modules by setting window.varName = varName; as
needed in the js files.
Also adds a custom rule to eslint. Since the recommended way of extending
eslint is to create plugins as standalone npm packages, the separate rule
is published as 'eslint-plugins-empty-returns'.
Fixes#8669.
Anders Kaseorg
Armaan Ahluwalia
Rohitt Vashishtha
Umair Khan
Brock Whittaker
Rafid Aslam
Leo Franchi