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-rw-r--r--node_modules/sucrase/dist/esm/parser/plugins/jsx/index.js367
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diff --git a/node_modules/sucrase/dist/esm/parser/plugins/jsx/index.js b/node_modules/sucrase/dist/esm/parser/plugins/jsx/index.js
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+import {
+ eat,
+ finishToken,
+ getTokenFromCode,
+ IdentifierRole,
+ JSXRole,
+ match,
+ next,
+ skipSpace,
+ Token,
+} from "../../tokenizer/index";
+import {TokenType as tt} from "../../tokenizer/types";
+import {input, isTypeScriptEnabled, state} from "../../traverser/base";
+import {parseExpression, parseMaybeAssign} from "../../traverser/expression";
+import {expect, unexpected} from "../../traverser/util";
+import {charCodes} from "../../util/charcodes";
+import {IS_IDENTIFIER_CHAR, IS_IDENTIFIER_START} from "../../util/identifier";
+import {tsTryParseJSXTypeArgument} from "../typescript";
+
+/**
+ * Read token with JSX contents.
+ *
+ * In addition to detecting jsxTagStart and also regular tokens that might be
+ * part of an expression, this code detects the start and end of text ranges
+ * within JSX children. In order to properly count the number of children, we
+ * distinguish jsxText from jsxEmptyText, which is a text range that simplifies
+ * to the empty string after JSX whitespace trimming.
+ *
+ * It turns out that a JSX text range will simplify to the empty string if and
+ * only if both of these conditions hold:
+ * - The range consists entirely of whitespace characters (only counting space,
+ * tab, \r, and \n).
+ * - The range has at least one newline.
+ * This can be proven by analyzing any implementation of whitespace trimming,
+ * e.g. formatJSXTextLiteral in Sucrase or cleanJSXElementLiteralChild in Babel.
+ */
+function jsxReadToken() {
+ let sawNewline = false;
+ let sawNonWhitespace = false;
+ while (true) {
+ if (state.pos >= input.length) {
+ unexpected("Unterminated JSX contents");
+ return;
+ }
+
+ const ch = input.charCodeAt(state.pos);
+ if (ch === charCodes.lessThan || ch === charCodes.leftCurlyBrace) {
+ if (state.pos === state.start) {
+ if (ch === charCodes.lessThan) {
+ state.pos++;
+ finishToken(tt.jsxTagStart);
+ return;
+ }
+ getTokenFromCode(ch);
+ return;
+ }
+ if (sawNewline && !sawNonWhitespace) {
+ finishToken(tt.jsxEmptyText);
+ } else {
+ finishToken(tt.jsxText);
+ }
+ return;
+ }
+
+ // This is part of JSX text.
+ if (ch === charCodes.lineFeed) {
+ sawNewline = true;
+ } else if (ch !== charCodes.space && ch !== charCodes.carriageReturn && ch !== charCodes.tab) {
+ sawNonWhitespace = true;
+ }
+ state.pos++;
+ }
+}
+
+function jsxReadString(quote) {
+ state.pos++;
+ for (;;) {
+ if (state.pos >= input.length) {
+ unexpected("Unterminated string constant");
+ return;
+ }
+
+ const ch = input.charCodeAt(state.pos);
+ if (ch === quote) {
+ state.pos++;
+ break;
+ }
+ state.pos++;
+ }
+ finishToken(tt.string);
+}
+
+// Read a JSX identifier (valid tag or attribute name).
+//
+// Optimized version since JSX identifiers can't contain
+// escape characters and so can be read as single slice.
+// Also assumes that first character was already checked
+// by isIdentifierStart in readToken.
+
+function jsxReadWord() {
+ let ch;
+ do {
+ if (state.pos > input.length) {
+ unexpected("Unexpectedly reached the end of input.");
+ return;
+ }
+ ch = input.charCodeAt(++state.pos);
+ } while (IS_IDENTIFIER_CHAR[ch] || ch === charCodes.dash);
+ finishToken(tt.jsxName);
+}
+
+// Parse next token as JSX identifier
+function jsxParseIdentifier() {
+ nextJSXTagToken();
+}
+
+// Parse namespaced identifier.
+function jsxParseNamespacedName(identifierRole) {
+ jsxParseIdentifier();
+ if (!eat(tt.colon)) {
+ // Plain identifier, so this is an access.
+ state.tokens[state.tokens.length - 1].identifierRole = identifierRole;
+ return;
+ }
+ // Process the second half of the namespaced name.
+ jsxParseIdentifier();
+}
+
+// Parses element name in any form - namespaced, member
+// or single identifier.
+function jsxParseElementName() {
+ const firstTokenIndex = state.tokens.length;
+ jsxParseNamespacedName(IdentifierRole.Access);
+ let hadDot = false;
+ while (match(tt.dot)) {
+ hadDot = true;
+ nextJSXTagToken();
+ jsxParseIdentifier();
+ }
+ // For tags like <div> with a lowercase letter and no dots, the name is
+ // actually *not* an identifier access, since it's referring to a built-in
+ // tag name. Remove the identifier role in this case so that it's not
+ // accidentally transformed by the imports transform when preserving JSX.
+ if (!hadDot) {
+ const firstToken = state.tokens[firstTokenIndex];
+ const firstChar = input.charCodeAt(firstToken.start);
+ if (firstChar >= charCodes.lowercaseA && firstChar <= charCodes.lowercaseZ) {
+ firstToken.identifierRole = null;
+ }
+ }
+}
+
+// Parses any type of JSX attribute value.
+function jsxParseAttributeValue() {
+ switch (state.type) {
+ case tt.braceL:
+ next();
+ parseExpression();
+ nextJSXTagToken();
+ return;
+
+ case tt.jsxTagStart:
+ jsxParseElement();
+ nextJSXTagToken();
+ return;
+
+ case tt.string:
+ nextJSXTagToken();
+ return;
+
+ default:
+ unexpected("JSX value should be either an expression or a quoted JSX text");
+ }
+}
+
+// Parse JSX spread child, after already processing the {
+// Does not parse the closing }
+function jsxParseSpreadChild() {
+ expect(tt.ellipsis);
+ parseExpression();
+}
+
+// Parses JSX opening tag starting after "<".
+// Returns true if the tag was self-closing.
+// Does not parse the last token.
+function jsxParseOpeningElement(initialTokenIndex) {
+ if (match(tt.jsxTagEnd)) {
+ // This is an open-fragment.
+ return false;
+ }
+ jsxParseElementName();
+ if (isTypeScriptEnabled) {
+ tsTryParseJSXTypeArgument();
+ }
+ let hasSeenPropSpread = false;
+ while (!match(tt.slash) && !match(tt.jsxTagEnd) && !state.error) {
+ if (eat(tt.braceL)) {
+ hasSeenPropSpread = true;
+ expect(tt.ellipsis);
+ parseMaybeAssign();
+ // }
+ nextJSXTagToken();
+ continue;
+ }
+ if (
+ hasSeenPropSpread &&
+ state.end - state.start === 3 &&
+ input.charCodeAt(state.start) === charCodes.lowercaseK &&
+ input.charCodeAt(state.start + 1) === charCodes.lowercaseE &&
+ input.charCodeAt(state.start + 2) === charCodes.lowercaseY
+ ) {
+ state.tokens[initialTokenIndex].jsxRole = JSXRole.KeyAfterPropSpread;
+ }
+ jsxParseNamespacedName(IdentifierRole.ObjectKey);
+ if (match(tt.eq)) {
+ nextJSXTagToken();
+ jsxParseAttributeValue();
+ }
+ }
+ const isSelfClosing = match(tt.slash);
+ if (isSelfClosing) {
+ // /
+ nextJSXTagToken();
+ }
+ return isSelfClosing;
+}
+
+// Parses JSX closing tag starting after "</".
+// Does not parse the last token.
+function jsxParseClosingElement() {
+ if (match(tt.jsxTagEnd)) {
+ // Fragment syntax, so we immediately have a tag end.
+ return;
+ }
+ jsxParseElementName();
+}
+
+// Parses entire JSX element, including its opening tag
+// (starting after "<"), attributes, contents and closing tag.
+// Does not parse the last token.
+function jsxParseElementAt() {
+ const initialTokenIndex = state.tokens.length - 1;
+ state.tokens[initialTokenIndex].jsxRole = JSXRole.NoChildren;
+ let numExplicitChildren = 0;
+ const isSelfClosing = jsxParseOpeningElement(initialTokenIndex);
+ if (!isSelfClosing) {
+ nextJSXExprToken();
+ while (true) {
+ switch (state.type) {
+ case tt.jsxTagStart:
+ nextJSXTagToken();
+ if (match(tt.slash)) {
+ nextJSXTagToken();
+ jsxParseClosingElement();
+ // Key after prop spread takes precedence over number of children,
+ // since it means we switch to createElement, which doesn't care
+ // about number of children.
+ if (state.tokens[initialTokenIndex].jsxRole !== JSXRole.KeyAfterPropSpread) {
+ if (numExplicitChildren === 1) {
+ state.tokens[initialTokenIndex].jsxRole = JSXRole.OneChild;
+ } else if (numExplicitChildren > 1) {
+ state.tokens[initialTokenIndex].jsxRole = JSXRole.StaticChildren;
+ }
+ }
+ return;
+ }
+ numExplicitChildren++;
+ jsxParseElementAt();
+ nextJSXExprToken();
+ break;
+
+ case tt.jsxText:
+ numExplicitChildren++;
+ nextJSXExprToken();
+ break;
+
+ case tt.jsxEmptyText:
+ nextJSXExprToken();
+ break;
+
+ case tt.braceL:
+ next();
+ if (match(tt.ellipsis)) {
+ jsxParseSpreadChild();
+ nextJSXExprToken();
+ // Spread children are a mechanism to explicitly mark children as
+ // static, so count it as 2 children to satisfy the "more than one
+ // child" condition.
+ numExplicitChildren += 2;
+ } else {
+ // If we see {}, this is an empty pseudo-expression that doesn't
+ // count as a child.
+ if (!match(tt.braceR)) {
+ numExplicitChildren++;
+ parseExpression();
+ }
+ nextJSXExprToken();
+ }
+
+ break;
+
+ // istanbul ignore next - should never happen
+ default:
+ unexpected();
+ return;
+ }
+ }
+ }
+}
+
+// Parses entire JSX element from current position.
+// Does not parse the last token.
+export function jsxParseElement() {
+ nextJSXTagToken();
+ jsxParseElementAt();
+}
+
+// ==================================
+// Overrides
+// ==================================
+
+export function nextJSXTagToken() {
+ state.tokens.push(new Token());
+ skipSpace();
+ state.start = state.pos;
+ const code = input.charCodeAt(state.pos);
+
+ if (IS_IDENTIFIER_START[code]) {
+ jsxReadWord();
+ } else if (code === charCodes.quotationMark || code === charCodes.apostrophe) {
+ jsxReadString(code);
+ } else {
+ // The following tokens are just one character each.
+ ++state.pos;
+ switch (code) {
+ case charCodes.greaterThan:
+ finishToken(tt.jsxTagEnd);
+ break;
+ case charCodes.lessThan:
+ finishToken(tt.jsxTagStart);
+ break;
+ case charCodes.slash:
+ finishToken(tt.slash);
+ break;
+ case charCodes.equalsTo:
+ finishToken(tt.eq);
+ break;
+ case charCodes.leftCurlyBrace:
+ finishToken(tt.braceL);
+ break;
+ case charCodes.dot:
+ finishToken(tt.dot);
+ break;
+ case charCodes.colon:
+ finishToken(tt.colon);
+ break;
+ default:
+ unexpected();
+ }
+ }
+}
+
+function nextJSXExprToken() {
+ state.tokens.push(new Token());
+ state.start = state.pos;
+ jsxReadToken();
+}