LinkOut node doesn't return to LinkCall Node

[ralphwetzel]

@phoddie -- As the title says: A LinkOut node doesn't return to its LinkCall Node.

Test case

```js [ { "id": "5d96ad23f6c6c847", "type": "tab", "label": "Flow 15", "disabled": false, "info": "", "env": [], "_mcu": { "mcu": true } }, { "id": "cc2784ee66765e42", "type": "group", "z": "5d96ad23f6c6c847", "name": "Come here!", "style": { "label": true }, "nodes": [ "988cf8d2c744c76e", "4ea66c21ba624d51", "300e0c35ed5e6039" ], "x": 254, "y": 419, "w": 362, "h": 82 }, { "id": "6ed2343e18f0a785", "type": "inject", "z": "5d96ad23f6c6c847", "name": "", "props": [ { "p": "payload" }, { "p": "topic", "vt": "str" } ], "repeat": "", "crontab": "", "once": false, "onceDelay": 0.1, "topic": "", "payload": "", "payloadType": "date", "_mcu": { "mcu": true }, "x": 340, "y": 380, "wires": [ [ "1613d9f16b6133d2" ] ] }, { "id": "1613d9f16b6133d2", "type": "link call", "z": "5d96ad23f6c6c847", "name": "", "links": [ "988cf8d2c744c76e" ], "linkType": "static", "timeout": "30", "_mcu": { "mcu": true }, "x": 510, "y": 380, "wires": [ [ "1a9d7ab025d3035c" ] ] }, { "id": "988cf8d2c744c76e", "type": "link in", "z": "5d96ad23f6c6c847", "g": "cc2784ee66765e42", "name": "Come here!", "links": [], "_mcu": { "mcu": true }, "x": 295, "y": 460, "wires": [ [ "4ea66c21ba624d51" ] ] }, { "id": "4ea66c21ba624d51", "type": "change", "z": "5d96ad23f6c6c847", "g": "cc2784ee66765e42", "name": "payload > done", "rules": [ { "t": "set", "p": "payload", "pt": "msg", "to": "done", "tot": "str" } ], "action": "", "property": "", "from": "", "to": "", "reg": false, "_mcu": { "mcu": true }, "x": 430, "y": 460, "wires": [ [ "300e0c35ed5e6039" ] ] }, { "id": "300e0c35ed5e6039", "type": "link out", "z": "5d96ad23f6c6c847", "g": "cc2784ee66765e42", "name": "link out 82", "mode": "return", "links": [], "_mcu": { "mcu": true }, "x": 575, "y": 460, "wires": [] }, { "id": "1a9d7ab025d3035c", "type": "debug", "z": "5d96ad23f6c6c847", "name": "debug 55", "active": true, "tosidebar": true, "console": false, "tostatus": false, "complete": "false", "statusVal": "", "statusType": "auto", "_mcu": { "mcu": true }, "x": 680, "y": 380, "wires": [] } ] ```

https://github.com/phoddie/node-red-mcu/blob/6427d0e16c32c9d32d29d117ff5c59a79d6da51c/nodered.js#L951-L980

This is due to the fact, that if (links) { is true in line 961 for links === [] and nodered2mcu.js emits links: [], for this node.

    [...]
    node = nodes.next().value;  // link out - 300e0c35ed5e6039
    node.onStart({
        g: "cc2784ee66765e42",
        name: "link out 82",
        mode: "return",
        links: [],
    });
    [...]

I propose to switch the sequence of the if clauses - as the existence of msg._linkSource should be the trigger to return to the calling node.

    if (Array.isArray(msg._linkSource) && (msg._linkSource.length > 0)) { [...] }
    else if (links) { [...] }
    else { [...] }

[phoddie]

@ralphwetzel, thank you for the test case and analysis! The tests I created work, so something must be different. I'll take look.

[ralphwetzel]

There seems to be another issue related to the LinkCall topic:

The timeout value is - by reference to the UI - defined in seconds:

I'm yet pretty sure, Timer.set() takes the timeout value in ms.

https://github.com/phoddie/node-red-mcu/blob/6427d0e16c32c9d32d29d117ff5c59a79d6da51c/nodered.js#L923-L930

This currently creates numerous link error missingReturn warnings - as the timeout fired before the function call returns...

[phoddie]

Could you be using an out-of-date nodered2mcu? The preprocessing does the conversion from seconds to milliseconds.

[phoddie]

Interesting example. I never thought about putting a Link In node in the same flow as the Link Call node. I just tried this with the last MCU Edition (including the current nodered2mcu from the Moddable SDK) and it outputs a debug message with "done" as expected. I'm hoping that after you update, it will work for you as well.

[ralphwetzel]

Could you be using an out-of-date nodered2mcu?

Indeed. I'm pretty sure though that GitHub showed me (for the last several days) this commit as the current one - and now magically jumped forward. 😕 Anyway. I'll test with the latest version...

[ralphwetzel]

👍 Both observations are resolved w/ the current commits. Thank you!

[phoddie]

Glad it was that easy. Sorry for the headache. I did learn that Link nodes can link into their own flow from this.