packages/babel-generator/src/generators/statements.js
import * as t from "@babel/types";
export function WithStatement(node: Object) {
this.word("with");
this.space();
this.token("(");
this.print(node.object, node);
this.token(")");
this.printBlock(node);
}
export function IfStatement(node: Object) {
this.word("if");
this.space();
this.token("(");
this.print(node.test, node);
this.token(")");
this.space();
const needsBlock =
node.alternate && t.isIfStatement(getLastStatement(node.consequent));
if (needsBlock) {
this.token("{");
this.newline();
this.indent();
}
this.printAndIndentOnComments(node.consequent, node);
if (needsBlock) {
this.dedent();
this.newline();
this.token("}");
}
if (node.alternate) {
if (this.endsWith("}")) this.space();
this.word("else");
this.space();
this.printAndIndentOnComments(node.alternate, node);
}
}
// Recursively get the last statement.
function getLastStatement(statement) {
if (!t.isStatement(statement.body)) return statement;
return getLastStatement(statement.body);
}
export function ForStatement(node: Object) {
this.word("for");
this.space();
this.token("(");
this.inForStatementInitCounter++;
this.print(node.init, node);
this.inForStatementInitCounter--;
this.token(";");
if (node.test) {
this.space();
this.print(node.test, node);
}
this.token(";");
if (node.update) {
this.space();
this.print(node.update, node);
}
this.token(")");
this.printBlock(node);
}
export function WhileStatement(node: Object) {
this.word("while");
this.space();
this.token("(");
this.print(node.test, node);
this.token(")");
this.printBlock(node);
}
const buildForXStatement = function (op) {
return function (node: Object) {
this.word("for");
this.space();
if (op === "of" && node.await) {
this.word("await");
this.space();
}
this.token("(");
this.print(node.left, node);
this.space();
this.word(op);
this.space();
this.print(node.right, node);
this.token(")");
this.printBlock(node);
};
};
export const ForInStatement = buildForXStatement("in");
export const ForOfStatement = buildForXStatement("of");
export function DoWhileStatement(node: Object) {
this.word("do");
this.space();
this.print(node.body, node);
this.space();
this.word("while");
this.space();
this.token("(");
this.print(node.test, node);
this.token(")");
this.semicolon();
}
function buildLabelStatement(prefix, key = "label") {
return function (node: Object) {
this.word(prefix);
const label = node[key];
if (label) {
this.space();
const isLabel = key == "label";
const terminatorState = this.startTerminatorless(isLabel);
this.print(label, node);
this.endTerminatorless(terminatorState);
}
this.semicolon();
};
}
export const ContinueStatement = buildLabelStatement("continue");
export const ReturnStatement = buildLabelStatement("return", "argument");
export const BreakStatement = buildLabelStatement("break");
export const ThrowStatement = buildLabelStatement("throw", "argument");
export function LabeledStatement(node: Object) {
this.print(node.label, node);
this.token(":");
this.space();
this.print(node.body, node);
}
export function TryStatement(node: Object) {
this.word("try");
this.space();
this.print(node.block, node);
this.space();
// Esprima bug puts the catch clause in a `handlers` array.
// see https://code.google.com/p/esprima/issues/detail?id=433
// We run into this from regenerator generated ast.
if (node.handlers) {
this.print(node.handlers[0], node);
} else {
this.print(node.handler, node);
}
if (node.finalizer) {
this.space();
this.word("finally");
this.space();
this.print(node.finalizer, node);
}
}
export function CatchClause(node: Object) {
this.word("catch");
this.space();
if (node.param) {
this.token("(");
this.print(node.param, node);
this.token(")");
this.space();
}
this.print(node.body, node);
}
export function SwitchStatement(node: Object) {
this.word("switch");
this.space();
this.token("(");
this.print(node.discriminant, node);
this.token(")");
this.space();
this.token("{");
this.printSequence(node.cases, node, {
indent: true,
addNewlines(leading, cas) {
if (!leading && node.cases[node.cases.length - 1] === cas) return -1;
},
});
this.token("}");
}
export function SwitchCase(node: Object) {
if (node.test) {
this.word("case");
this.space();
this.print(node.test, node);
this.token(":");
} else {
this.word("default");
this.token(":");
}
if (node.consequent.length) {
this.newline();
this.printSequence(node.consequent, node, { indent: true });
}
}
export function DebuggerStatement() {
this.word("debugger");
this.semicolon();
}
function variableDeclarationIndent() {
// "let " or "var " indentation.
this.token(",");
this.newline();
if (this.endsWith("\n")) for (let i = 0; i < 4; i++) this.space(true);
}
function constDeclarationIndent() {
// "const " indentation.
this.token(",");
this.newline();
if (this.endsWith("\n")) for (let i = 0; i < 6; i++) this.space(true);
}
export function VariableDeclaration(node: Object, parent: Object) {
if (node.declare) {
// TS
this.word("declare");
this.space();
}
this.word(node.kind);
this.space();
let hasInits = false;
// don't add whitespace to loop heads
if (!t.isFor(parent)) {
for (const declar of (node.declarations: Array<Object>)) {
if (declar.init) {
// has an init so let's split it up over multiple lines
hasInits = true;
}
}
}
//
// use a pretty separator when we aren't in compact mode, have initializers and don't have retainLines on
// this will format declarations like:
//
// let foo = "bar", bar = "foo";
//
// into
//
// let foo = "bar",
// bar = "foo";
//
let separator;
if (hasInits) {
separator =
node.kind === "const"
? constDeclarationIndent
: variableDeclarationIndent;
}
//
this.printList(node.declarations, node, { separator });
if (t.isFor(parent)) {
// don't give semicolons to these nodes since they'll be inserted in the parent generator
if (parent.left === node || parent.init === node) return;
}
this.semicolon();
}
export function VariableDeclarator(node: Object) {
this.print(node.id, node);
if (node.definite) this.token("!"); // TS
this.print(node.id.typeAnnotation, node);
if (node.init) {
this.space();
this.token("=");
this.space();
this.print(node.init, node);
}
}