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1 files changed, 367 insertions, 0 deletions

diff --git a/node_modules/sucrase/dist/esm/parser/plugins/jsx/index.js b/node_modules/sucrase/dist/esm/parser/plugins/jsx/index.js
new file mode 100644
index 0000000..83f3983
--- /dev/null
+++ b/node_modules/sucrase/dist/esm/parser/plugins/jsx/index.js
@@ -0,0 +1,367 @@
+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();
+}