jsparse.c

一个基于alice开发的机器人

        pn->pn_op = JSOP_IMPORTPROP;
        break;
      case JSOP_GETELEM:
        pn->pn_op = JSOP_IMPORTELEM;
        break;
      case JSOP_IMPORTALL:
        break;
      default:
        goto bad_import;
    }
    return pn;

  bad_import:
    js_ReportCompileErrorNumber(cx, ts, NULL, JSREPORT_ERROR, JSMSG_BAD_IMPORT);
    return NULL;
}
#endif /* JS_HAS_EXPORT_IMPORT */

extern const char js_with_statement_str[];

static JSParseNode *
Statement(JSContext *cx, JSTokenStream *ts, JSTreeContext *tc)
{
    JSTokenType tt;
    JSParseNode *pn, *pn1, *pn2, *pn3, *pn4;
    JSStmtInfo stmtInfo, *stmt, *stmt2;
    JSAtom *label;

    ts->flags |= TSF_REGEXP;
    tt = js_GetToken(cx, ts);
    ts->flags &= ~TSF_REGEXP;

#if JS_HAS_GETTER_SETTER
    if (tt == TOK_NAME) {
        tt = CheckGetterOrSetter(cx, ts, TOK_FUNCTION);
        if (tt == TOK_ERROR)
            return NULL;
    }
#endif

    switch (tt) {
#if JS_HAS_EXPORT_IMPORT
      case TOK_EXPORT:
        pn = NewParseNode(cx, &CURRENT_TOKEN(ts), PN_LIST, tc);
        if (!pn)
            return NULL;
        PN_INIT_LIST(pn);
        if (js_MatchToken(cx, ts, TOK_STAR)) {
            pn2 = NewParseNode(cx, &CURRENT_TOKEN(ts), PN_NULLARY, tc);
            if (!pn2)
                return NULL;
            PN_APPEND(pn, pn2);
        } else {
            do {
                MUST_MATCH_TOKEN(TOK_NAME, JSMSG_NO_EXPORT_NAME);
                pn2 = NewParseNode(cx, &CURRENT_TOKEN(ts), PN_NAME, tc);
                if (!pn2)
                    return NULL;
                pn2->pn_op = JSOP_NAME;
                pn2->pn_atom = CURRENT_TOKEN(ts).t_atom;
                pn2->pn_expr = NULL;
                pn2->pn_slot = -1;
                pn2->pn_attrs = 0;
                PN_APPEND(pn, pn2);
            } while (js_MatchToken(cx, ts, TOK_COMMA));
        }
        pn->pn_pos.end = PN_LAST(pn)->pn_pos.end;
        tc->flags |= TCF_FUN_HEAVYWEIGHT;
        break;

      case TOK_IMPORT:
        pn = NewParseNode(cx, &CURRENT_TOKEN(ts), PN_LIST, tc);
        if (!pn)
            return NULL;
        PN_INIT_LIST(pn);
        do {
            pn2 = ImportExpr(cx, ts, tc);
            if (!pn2)
                return NULL;
            PN_APPEND(pn, pn2);
        } while (js_MatchToken(cx, ts, TOK_COMMA));
        pn->pn_pos.end = PN_LAST(pn)->pn_pos.end;
        tc->flags |= TCF_FUN_HEAVYWEIGHT;
        break;
#endif /* JS_HAS_EXPORT_IMPORT */

      case TOK_FUNCTION:
        return FunctionStmt(cx, ts, tc);

      case TOK_IF:
        /* An IF node has three kids: condition, then, and optional else. */
        pn = NewParseNode(cx, &CURRENT_TOKEN(ts), PN_TERNARY, tc);
        if (!pn)
            return NULL;
        pn1 = Condition(cx, ts, tc);
        if (!pn1)
            return NULL;
        js_PushStatement(tc, &stmtInfo, STMT_IF, -1);
        pn2 = Statement(cx, ts, tc);
        if (!pn2)
            return NULL;
        if (js_MatchToken(cx, ts, TOK_ELSE)) {
            stmtInfo.type = STMT_ELSE;
            pn3 = Statement(cx, ts, tc);
            if (!pn3)
                return NULL;
            pn->pn_pos.end = pn3->pn_pos.end;
        } else {
            pn3 = NULL;
            pn->pn_pos.end = pn2->pn_pos.end;
        }
        js_PopStatement(tc);
        pn->pn_kid1 = pn1;
        pn->pn_kid2 = pn2;
        pn->pn_kid3 = pn3;
        return pn;

#if JS_HAS_SWITCH_STATEMENT
      case TOK_SWITCH:
      {
        JSParseNode *pn5;
        JSBool seenDefault = JS_FALSE;

        pn = NewParseNode(cx, &CURRENT_TOKEN(ts), PN_BINARY, tc);
        if (!pn)
            return NULL;
        MUST_MATCH_TOKEN(TOK_LP, JSMSG_PAREN_BEFORE_SWITCH);

        /* pn1 points to the switch's discriminant. */
        pn1 = Expr(cx, ts, tc);
        if (!pn1)
            return NULL;

        MUST_MATCH_TOKEN(TOK_RP, JSMSG_PAREN_AFTER_SWITCH);
        MUST_MATCH_TOKEN(TOK_LC, JSMSG_CURLY_BEFORE_SWITCH);

        /* pn2 is a list of case nodes. The default case has pn_left == NULL */
        pn2 = NewParseNode(cx, &CURRENT_TOKEN(ts), PN_LIST, tc);
        if (!pn2)
            return NULL;
        PN_INIT_LIST(pn2);

        js_PushStatement(tc, &stmtInfo, STMT_SWITCH, -1);

        while ((tt = js_GetToken(cx, ts)) != TOK_RC) {
            switch (tt) {
              case TOK_DEFAULT:
                if (seenDefault) {
                    js_ReportCompileErrorNumber(cx, ts, NULL, JSREPORT_ERROR,
                                                JSMSG_TOO_MANY_DEFAULTS);
                    return NULL;
                }
                seenDefault = JS_TRUE;
                /* fall through */

              case TOK_CASE:
                pn3 = NewParseNode(cx, &CURRENT_TOKEN(ts), PN_BINARY, tc);
                if (!pn3)
                    return NULL;
                if (tt == TOK_DEFAULT) {
                    pn3->pn_left = NULL;
                } else {
                    pn3->pn_left = Expr(cx, ts, tc);
                    if (!pn3->pn_left)
                        return NULL;
                }
                PN_APPEND(pn2, pn3);
                if (pn2->pn_count == JS_BIT(16)) {
                    js_ReportCompileErrorNumber(cx, ts, NULL, JSREPORT_ERROR,
                                                JSMSG_TOO_MANY_CASES);
                    return NULL;
                }
                break;

              case TOK_ERROR:
                return NULL;

              default:
                js_ReportCompileErrorNumber(cx, ts, NULL, JSREPORT_ERROR,
                                            JSMSG_BAD_SWITCH);
                return NULL;
            }
            MUST_MATCH_TOKEN(TOK_COLON, JSMSG_COLON_AFTER_CASE);

            pn4 = NewParseNode(cx, &CURRENT_TOKEN(ts), PN_LIST, tc);
            if (!pn4)
                return NULL;
            pn4->pn_type = TOK_LC;
            PN_INIT_LIST(pn4);
            while ((tt = js_PeekToken(cx, ts)) != TOK_RC &&
                   tt != TOK_CASE && tt != TOK_DEFAULT) {
                if (tt == TOK_ERROR)
                    return NULL;
                pn5 = Statement(cx, ts, tc);
                if (!pn5)
                    return NULL;
                pn4->pn_pos.end = pn5->pn_pos.end;
                PN_APPEND(pn4, pn5);
            }

            /* Fix the PN_LIST so it doesn't begin at the TOK_COLON. */
            if (pn4->pn_head)
                pn4->pn_pos.begin = pn4->pn_head->pn_pos.begin;
            pn3->pn_pos.end = pn4->pn_pos.end;
            pn3->pn_right = pn4;
        }

        js_PopStatement(tc);

        pn->pn_pos.end = pn2->pn_pos.end = CURRENT_TOKEN(ts).pos.end;
        pn->pn_kid1 = pn1;
        pn->pn_kid2 = pn2;
        return pn;
      }
#endif /* JS_HAS_SWITCH_STATEMENT */

      case TOK_WHILE:
        pn = NewParseNode(cx, &CURRENT_TOKEN(ts), PN_BINARY, tc);
        if (!pn)
            return NULL;
        js_PushStatement(tc, &stmtInfo, STMT_WHILE_LOOP, -1);
        pn2 = Condition(cx, ts, tc);
        if (!pn2)
            return NULL;
        pn->pn_left = pn2;
        pn2 = Statement(cx, ts, tc);
        if (!pn2)
            return NULL;
        js_PopStatement(tc);
        pn->pn_pos.end = pn2->pn_pos.end;
        pn->pn_right = pn2;
        return pn;

#if JS_HAS_DO_WHILE_LOOP
      case TOK_DO:
        pn = NewParseNode(cx, &CURRENT_TOKEN(ts), PN_BINARY, tc);
        if (!pn)
            return NULL;
        js_PushStatement(tc, &stmtInfo, STMT_DO_LOOP, -1);
        pn2 = Statement(cx, ts, tc);
        if (!pn2)
            return NULL;
        pn->pn_left = pn2;
        MUST_MATCH_TOKEN(TOK_WHILE, JSMSG_WHILE_AFTER_DO);
        pn2 = Condition(cx, ts, tc);
        if (!pn2)
            return NULL;
        js_PopStatement(tc);
        pn->pn_pos.end = pn2->pn_pos.end;
        pn->pn_right = pn2;
        break;
#endif /* JS_HAS_DO_WHILE_LOOP */

      case TOK_FOR:
        /* A FOR node is binary, left is loop control and right is the body. */
        pn = NewParseNode(cx, &CURRENT_TOKEN(ts), PN_BINARY, tc);
        if (!pn)
            return NULL;
        js_PushStatement(tc, &stmtInfo, STMT_FOR_LOOP, -1);

        MUST_MATCH_TOKEN(TOK_LP, JSMSG_PAREN_AFTER_FOR);
        tt = js_PeekToken(cx, ts);
        if (tt == TOK_SEMI) {
            /* No initializer -- set first kid of left sub-node to null. */
            pn1 = NULL;
        } else {
            /* Set pn1 to a var list or an initializing expression. */
#if JS_HAS_IN_OPERATOR
            /*
             * Set the TCF_IN_FOR_INIT flag during parsing of the first clause
             * of the for statement.  This flag will be used by the RelExpr
             * production; if it is set, then the 'in' keyword will not be
             * recognized as an operator, leaving it available to be parsed as
             * part of a for/in loop.  A side effect of this restriction is
             * that (unparenthesized) expressions involving an 'in' operator
             * are illegal in the init clause of an ordinary for loop.
             */
            tc->flags |= TCF_IN_FOR_INIT;
#endif /* JS_HAS_IN_OPERATOR */
            if (tt == TOK_VAR) {
                (void) js_GetToken(cx, ts);
                pn1 = Variables(cx, ts, tc);
            } else {
                pn1 = Expr(cx, ts, tc);
            }
#if JS_HAS_IN_OPERATOR
            tc->flags &= ~TCF_IN_FOR_INIT;
#endif /* JS_HAS_IN_OPERATOR */
            if (!pn1)
                return NULL;
        }

        /*
         * We can be sure that it's a for/in loop if there's still an 'in'
         * keyword here, even if JavaScript recognizes 'in' as an operator,
         * as we've excluded 'in' from being parsed in RelExpr by setting
         * the TCF_IN_FOR_INIT flag in our JSTreeContext.
         */
        if (pn1 && js_MatchToken(cx, ts, TOK_IN)) {
            stmtInfo.type = STMT_FOR_IN_LOOP;

            /* Check that the left side of the 'in' is valid. */
            if ((pn1->pn_type == TOK_VAR)
                ? (pn1->pn_count > 1 || pn1->pn_op == JSOP_DEFCONST)
                : (pn1->pn_type != TOK_NAME &&
                   pn1->pn_type != TOK_DOT &&
                   pn1->pn_type != TOK_LB)) {
                js_ReportCompileErrorNumber(cx, ts, NULL, JSREPORT_ERROR,
                                            JSMSG_BAD_FOR_LEFTSIDE);
                return NULL;
            }

            if (pn1->pn_type == TOK_VAR) {
                /* Tell js_EmitTree(TOK_VAR) to generate a final POP. */
                pn1->pn_extra = JS_TRUE;
                pn2 = pn1->pn_head;
            } else {
                pn2 = pn1;
            }

            /* Beware 'for (arguments in ...)' with or without a 'var'. */
            if (pn2->pn_type == TOK_NAME &&
                pn2->pn_atom == cx->runtime->atomState.argumentsAtom) {
                tc->flags |= TCF_FUN_HEAVYWEIGHT;
            }

            /* Parse the object expression as the right operand of 'in'. */
            pn2 = NewBinary(cx, TOK_IN, JSOP_NOP, pn1, Expr(cx, ts, tc), tc);
            if (!pn2)
                return NULL;
            pn->pn_left = pn2;
        } else {
            /* Parse the loop condition or null into pn2. */
            MUST_MATCH_TOKEN(TOK_SEMI, JSMSG_SEMI_AFTER_FOR_INIT);
            if (js_PeekToken(cx, ts) == TOK_SEMI) {
                pn2 = NULL;
            } else {
                pn2 = Expr(cx, ts, tc);
                if (!pn2)
                    return NULL;
            }

            /* Parse the update expression or null into pn3. */
            MUST_MATCH_TOKEN(TOK_SEMI, JSMSG_SEMI_AFTER_FOR_COND);
            if (js_PeekToken(cx, ts) == TOK_RP) {
                pn3 = NULL;
            } else {
                pn3 = Expr(cx, ts, tc);
                if (!pn3)
                    return NULL;
            }

            /* Build the RESERVED node to use as the left kid of pn. */
            pn4 = NewParseNode(cx, &CURRENT_TOKEN(ts), PN_TERNARY, tc);
            if (!pn4)
                return NULL;
            pn4->pn_type = TOK_RESERVED;
            pn4->pn_op = JSOP_NOP;
            pn4->pn_kid1 = pn1;
            pn4->pn_kid2 = pn2;
            pn4->pn_kid3 = pn3;
            pn->pn_left = pn4;
        }

        MUST_MATCH_TOKEN(TOK_RP, JSMSG_PAREN_AFTER_FOR_CTRL);

        /* Parse the loop body into pn->pn_right. */
        pn2 = Statement(cx, ts, tc);
        if (!pn2)
            return NULL;
        pn->pn_right = pn2;
        js_PopStatement(tc);

        /* Record the absolute line number for source note emission. */
        pn->pn_pos.end = pn2->pn_pos.end;
        return pn;

#if JS_HAS_EXCEPTIONS
      case TOK_TRY: {
        JSParseNode *catchtail = NULL;
        /*
         * try nodes are ternary.
         * kid1 is the try Statement
         * kid2 is the catch node