Anders Kaseorg
02511bff1c
js: Automatically convert _.each to for…of.
...
This commit was automatically generated by the following script,
followed by lint --fix and a few small manual lint-related cleanups.
import * as babelParser from "recast/parsers/babel";
import * as recast from "recast";
import * as tsParser from "recast/parsers/typescript";
import { builders as b, namedTypes as n } from "ast-types";
import { Context } from "ast-types/lib/path-visitor";
import K from "ast-types/gen/kinds";
import { NodePath } from "ast-types/lib/node-path";
import assert from "assert";
import fs from "fs";
import path from "path";
import process from "process";
const checkExpression = (node: n.Node): node is K.ExpressionKind =>
n.Expression.check(node);
const checkStatement = (node: n.Node): node is K.StatementKind =>
n.Statement.check(node);
for (const file of process.argv.slice(2)) {
console.log("Parsing", file);
const ast = recast.parse(fs.readFileSync(file, { encoding: "utf8" }), {
parser: path.extname(file) === ".ts" ? tsParser : babelParser,
});
let changed = false;
let inLoop = false;
let replaceReturn = false;
const visitLoop = (...args: string[]) =>
function(this: Context, path: NodePath) {
for (const arg of args) {
this.visit(path.get(arg));
}
const old = { inLoop };
inLoop = true;
this.visit(path.get("body"));
inLoop = old.inLoop;
return false;
};
recast.visit(ast, {
visitDoWhileStatement: visitLoop("test"),
visitExpressionStatement(path) {
const { expression, comments } = path.node;
let valueOnly;
if (
n.CallExpression.check(expression) &&
n.MemberExpression.check(expression.callee) &&
!expression.callee.computed &&
n.Identifier.check(expression.callee.object) &&
expression.callee.object.name === "_" &&
n.Identifier.check(expression.callee.property) &&
["each", "forEach"].includes(expression.callee.property.name) &&
[2, 3].includes(expression.arguments.length) &&
checkExpression(expression.arguments[0]) &&
(n.FunctionExpression.check(expression.arguments[1]) ||
n.ArrowFunctionExpression.check(expression.arguments[1])) &&
[1, 2].includes(expression.arguments[1].params.length) &&
n.Identifier.check(expression.arguments[1].params[0]) &&
((valueOnly = expression.arguments[1].params[1] === undefined) ||
n.Identifier.check(expression.arguments[1].params[1])) &&
(expression.arguments[2] === undefined ||
n.ThisExpression.check(expression.arguments[2]))
) {
const old = { inLoop, replaceReturn };
inLoop = false;
replaceReturn = true;
this.visit(
path
.get("expression")
.get("arguments")
.get(1)
.get("body")
);
inLoop = old.inLoop;
replaceReturn = old.replaceReturn;
const [right, { body, params }] = expression.arguments;
const loop = b.forOfStatement(
b.variableDeclaration("let", [
b.variableDeclarator(
valueOnly ? params[0] : b.arrayPattern([params[1], params[0]])
),
]),
valueOnly
? right
: b.callExpression(
b.memberExpression(right, b.identifier("entries")),
[]
),
checkStatement(body) ? body : b.expressionStatement(body)
);
loop.comments = comments;
path.replace(loop);
changed = true;
}
this.traverse(path);
},
visitForStatement: visitLoop("init", "test", "update"),
visitForInStatement: visitLoop("left", "right"),
visitForOfStatement: visitLoop("left", "right"),
visitFunction(path) {
this.visit(path.get("params"));
const old = { replaceReturn };
replaceReturn = false;
this.visit(path.get("body"));
replaceReturn = old.replaceReturn;
return false;
},
visitReturnStatement(path) {
if (replaceReturn) {
assert(!inLoop); // could use labeled continue if this ever fires
const { argument, comments } = path.node;
if (argument === null) {
const s = b.continueStatement();
s.comments = comments;
path.replace(s);
} else {
const s = b.expressionStatement(argument);
s.comments = comments;
path.replace(s, b.continueStatement());
}
return false;
}
this.traverse(path);
},
visitWhileStatement: visitLoop("test"),
});
if (changed) {
console.log("Writing", file);
fs.writeFileSync(file, recast.print(ast).code, { encoding: "utf8" });
}
}
Signed-off-by: Anders Kaseorg <anders@zulipchat.com>
2020-02-07 14:09:47 -08:00
Steve Howell
fa82d12525
topic list: Extract topic_list_data.js.
...
This is mostly for tactical reasons. It's hard to
get 100% test coverage on topic_list.js, but it
should be easy to get 100% test coverage on this
very important function.
I considered just moving this code into topic_data.js,
but it just didn't feel quite right. I feel like
this is a pretty core piece of code that's nice
to be by itself and not be near other complicated
code that does stuff like build widgets or talk
to servers. (And, again, it's not just the actual
code here, which is pretty small, it's the unit
tests, which are inherently verbose to exercise
all the edge cases.)
2020-01-22 14:31:33 -08:00