Declare variables before use #6806
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Gudahtt
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While working on MetaMask#6805, I noticed that many variables were being used before they were declared. Technically this worked fine in practice because we were using the `transform-es2015-block-scoping` Babel plugin, which transforms `let` and `const` to `var`, which is hoisted. However, after removing that Babel transformation, many things broke. All instances of variables or classes being used before declared have been fixed. The `no-use-before-define` eslint rule has been added to catch these cases going forward. The rule is disabled for function declarations for the moment, because those are always hoisted. We could disable that too if we want to, but it's purely stylistic and would require a lot more changes.
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While working on #6805, I noticed that many variables were being used before they were declared. Technically this worked fine in practice because we were using the
transform-es2015-block-scopingBabel plugin, which transformsletandconsttovar, which is hoisted. However, after removing that Babel transformation, many things broke.All instances of variables or classes being used before declared have been fixed.
The
no-use-before-defineeslint rule has been added to catch these cases going forward. The rule is disabled for function declarations for the moment, because those are always hoisted. We could disable that too if we want to, but it's purely stylistic and would require a lot more changes.