src/addons/addons/editor-block-chomping/userscript.js

export default async function ({ addon }) {
    const ScratchBlocks = await addon.tab.traps.getBlockly();

    // Rerender the dragged block when updating the insertion marker
    const ogConnectMarker = ScratchBlocks.InsertionMarkerManager.prototype.connectMarker_;
    ScratchBlocks.InsertionMarkerManager.prototype.connectMarker_ = function () {
        ogConnectMarker.call(this);
        if (!addon.self.disabled && this.firstMarker_) {
            const block = this?.workspace_?.currentGesture_?.blockDragger_?.draggingBlock_;
            block.noMoveConnection = true;
            if (block) block.render(false);
        }
    };
    const ogDisconnectMarker = ScratchBlocks.InsertionMarkerManager.prototype.disconnectMarker_;
    ScratchBlocks.InsertionMarkerManager.prototype.disconnectMarker_ = function () {
        ogDisconnectMarker.call(this);
        if (!addon.self.disabled && this.firstMarker_) {
            const block = this?.workspace_?.currentGesture_?.blockDragger_?.draggingBlock_;
            block.noMoveConnection = true;
            if (block) block.render(false);
        }
    };

    const ogDraw = ScratchBlocks.BlockSvg.prototype.renderDraw_;
    const ogMoveConnections = ScratchBlocks.BlockSvg.prototype.renderMoveConnections_;
    ScratchBlocks.BlockSvg.prototype.renderDraw_ = function (iconWidth, inputRows) {
        if (addon.self.disabled) return ogDraw.call(this, iconWidth, inputRows);

        // If the block contains a statement (C) input and has an insertion marker,
        // use that to calculate the height of the statement inputs
        let computeBlock = this;
        if (this?.workspace?.currentGesture_?.blockDragger_?.draggedConnectionManager_) {
            const dragger = this.workspace.currentGesture_.blockDragger_;
            const manager = dragger.draggedConnectionManager_;
            if (
                manager.markerConnection_ &&
                manager.firstMarker_ &&
                dragger.draggingBlock_ == this &&
                dragger.draggingBlock_.type == manager.firstMarker_.type
            ) {
                if (inputRows.some((row) => row.some((input) => input.type === ScratchBlocks.NEXT_STATEMENT))) {
                    computeBlock = manager.firstMarker_;
                }
            }
        }

        // Change the height of substacks
        // (If we set inputRows to computeBlock.renderCompute_,
        // the references to the inputs would be wrong
        // so they just won't update properly)
        if (computeBlock !== this) {
            const _inputRows = computeBlock.renderCompute_(iconWidth);
            for (let i = 0; i < inputRows.length; i++) {
                const row = inputRows[i];
                let update = false;
                for (const input of row) {
                    if (input.type === ScratchBlocks.NEXT_STATEMENT) update = true;
                }
                if (update) row.height = Math.max(row.height, _inputRows[i].height);
            }
        }

        ogDraw.call(this, iconWidth, inputRows);

        // Moving the connections of a block while it's being dragged breaks it,
        // so don't
        if (computeBlock === this && !this.noMoveConnection) ogMoveConnections.call(this);
        this.noMoveConnection = false;
    };
    ScratchBlocks.BlockSvg.prototype.renderMoveConnections_ = function () {
        if (addon.self.disabled) return ogMoveConnections.call(this);
        // Do nothing (this function is instead called by renderDraw_)
    };
}