5 releases
0.2.11 | Jan 30, 2023 |
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0.2.10 | Jan 30, 2023 |
0.2.2 | Dec 22, 2022 |
0.2.1 | Dec 22, 2022 |
0.2.0 | Dec 22, 2022 |
#1816 in Parser implementations
18KB
266 lines
swc-plugin-dev-expression
A port of Facebook's dev-expression Babel plugin.
This plugin gates calls to warning()
behind process.env.NODE_ENV !== 'production'
, modifies calls to invariant()
to hoist the condition outside of the function call, and replaces __DEV__
expressions with a NODE_ENV
check. Most bundlers will then strip these calls out of production code entirely. The transform applied to warning()
and invariant()
is identical to the behaviour of babel-plugin-dev-expression
. The transformation of __DEV__
differs and is only done in more constrained conditions, for ease of implementation. See note below.
invariant
Replaces
invariant(condition, argument, argument);
with
if (!condition) {
if ("production" !== process.env.NODE_ENV) {
invariant(false, argument, argument);
} else {
invariant(false);
}
}
Recommended for use with https://github.com/zertosh/invariant or smaller https://github.com/alexreardon/tiny-invariant.
warning
Replaces
warning(condition, argument, argument);
with
if ("production" !== process.env.NODE_ENV) {
warning(condition, argument, argument);
}
Recommended for use with https://github.com/r3dm/warning or smaller https://github.com/alexreardon/tiny-warning.
__DEV__
Replaces
if (__DEV__) {}
(__DEV__ ? yes() : no());
!__DEV__;
(__DEV__ && true);
(__DEV__ || false);
with
if(process.env.NODE_ENV !== 'production') {}
(process.env.NODE_ENV !== 'production' ? yes() : no());
!(process.env.NODE_ENV !== 'production');
(process.env.NODE_ENV !== 'production') && true;
(process.env.NODE_ENV !== 'production') || false;
Note: The plugin does not transform every single reference to __DEV__
. It will only make this substitution if __DEV__
is the entire condition in an if
statement or ?
conditional expression, or if __DEV__
is an argument to a logical expression (!
, &&
or ||
). If this limitation poses any problems for your usage, please get in touch.
## License This project is Copyright of Angel Wells, licenced under GPL 3.0 or later.
Dependencies
~5–11MB
~142K SLoC