Starting PyPromise

runtime-pyside6/LogarithmPlotter/qml/eu/ad5001/LogarithmPlotter/Popup/Changelog.qml

@@ -45,17 +45,17 @@ Popup {
     property bool changelogNeedsFetching: true
     
     onAboutToShow: if(changelogNeedsFetching) {
-        Helper.fetchChangelog()
-    }
-    
-    Connections {
-        target: Helper
-        function onChangelogFetched(chl) {
-            changelogNeedsFetching = false;
-            changelog.text = chl
+        Helper.fetchChangelog().then((fetchedText) => {
+            changelogNeedsFetching = false
+            changelog.text = fetchedText
             changelogView.contentItem.implicitHeight = changelog.height
-            // console.log(changelog.height, changelogView.contentItem.implicitHeight)
-        }
+        }, (error) => {
+            const e = qsTranslate("changelog", "Could not fetch update: {}.").replace('{}', error)
+            console.error(e)
+            changelogNeedsFetching = false
+            changelog.text = e
+            changelogView.contentItem.implicitHeight = changelog.height
+        })
     }
 
     ScrollView {

runtime-pyside6/LogarithmPlotter/util/helper.py

@@ -29,13 +29,16 @@ from urllib.error import HTTPError, URLError
 
 from LogarithmPlotter import __VERSION__
 from LogarithmPlotter.util import config
+from LogarithmPlotter.util.promise import PyPromise
 
 SHOW_GUI_MESSAGES = "--test-build" not in argv
 CHANGELOG_VERSION = __VERSION__
+CHANGELOG_CACHE_PATH = path.join(path.dirname(path.realpath(__file__)), "CHANGELOG.md")
 
 
 class InvalidFileException(Exception): pass
 
+
 def show_message(msg: str) -> None:
     """
     Shows a GUI message if GUI messages are enabled
@@ -46,13 +49,7 @@ def show_message(msg: str) -> None:
         raise InvalidFileException(msg)
 
 
-
-class ChangelogFetcher(QRunnable):
-    def __init__(self, helper):
-        QRunnable.__init__(self)
-        self.helper = helper
-
-    def run(self):
+def fetch_changelog():
     msg_text = "Unknown changelog error."
     try:
         # Fetching version
@@ -65,12 +62,17 @@ class ChangelogFetcher(QRunnable):
             str(e.code))
     except URLError as e:
         msg_text = QCoreApplication.translate("changelog", "Could not fetch update: {}.").format(str(e.reason))
-        self.helper.changelogFetched.emit(msg_text)
+    return msg_text
+
+
+def read_changelog():
+    f = open(CHANGELOG_CACHE_PATH, 'r', -1)
+    data = f.read().strip()
+    f.close()
+    return data
 
 
 class Helper(QObject):
-    changelogFetched = Signal(str)
-
     def __init__(self, cwd: str, tmpfile: str):
         QObject.__init__(self)
         self.cwd = cwd
@@ -150,15 +152,14 @@ class Helper(QObject):
         msg = QCoreApplication.translate('main', "Built with PySide6 (Qt) v{} and python v{}")
         return msg.format(PySide6_version, sys_version.split("\n")[0])
 
-    @Slot()
+    @Slot(result=PyPromise)
     def fetchChangelog(self):
-        changelog_cache_path = path.join(path.dirname(path.realpath(__file__)), "CHANGELOG.md")
-        if path.exists(changelog_cache_path):
+        """
+        Fetches the changelog and returns a Promise.
+        """
+        if path.exists(CHANGELOG_CACHE_PATH):
             # We have a cached version of the changelog, for env that don't have access to the internet.
-            f = open(changelog_cache_path);
-            self.changelogFetched.emit("".join(f.readlines()).strip())
-            f.close()
+            return PyPromise(read_changelog)
         else:
             # Fetch it from the internet.
-            runnable = ChangelogFetcher(self)
-            QThreadPool.globalInstance().start(runnable)
+            return PyPromise(fetch_changelog)

runtime-pyside6/LogarithmPlotter/util/js.py

@@ -16,13 +16,13 @@
  *  along with this program.  If not, see <https://www.gnu.org/licenses/>.
 """
 from re import Pattern
+from typing import Callable
 from PySide6.QtCore import QMetaObject, QObject, QDateTime
 from PySide6.QtQml import QJSValue
 
 class InvalidAttributeValueException(Exception): pass
 class NotAPrimitiveException(Exception): pass
 
-class Function: pass
 class URL: pass
 
 class PyJSValue:
@@ -78,7 +78,7 @@ class PyJSValue:
         matcher = [
             (lambda: self.qjs_value.isArray(), list),
             (lambda: self.qjs_value.isBool(), bool),
-            (lambda: self.qjs_value.isCallable(), Function),
+            (lambda: self.qjs_value.isCallable(), Callable),
             (lambda: self.qjs_value.isDate(), QDateTime),
             (lambda: self.qjs_value.isError(), Exception),
             (lambda: self.qjs_value.isNull(), None),
@@ -104,3 +104,5 @@ class PyJSValue:
         if self.type() not in [bool, float, str, None]:
             raise NotAPrimitiveException()
         return self.qjs_value.toPrimitive().toVariant()
+
+

runtime-pyside6/LogarithmPlotter/util/latex.py

@@ -16,18 +16,17 @@
  *  along with this program.  If not, see <https://www.gnu.org/licenses/>.
 """
 
-from PySide6.QtCore import QObject, Slot, Property, QCoreApplication
+from PySide6.QtCore import QObject, Slot, Property, QCoreApplication, Signal
 from PySide6.QtGui import QImage, QColor
 from PySide6.QtWidgets import QMessageBox
 
-from os import path, remove, environ, makedirs
+from os import path, remove, makedirs
 from string import Template
 from subprocess import Popen, TimeoutExpired, PIPE
 from hashlib import sha512
 from shutil import which
 from sys import argv
 
-
 """
 Searches for a valid Latex and DVIPNG (http://savannah.nongnu.org/projects/dvipng/)
 installation and collects the binary path in the DVIPNG_PATH variable.
@@ -76,6 +75,7 @@ class Latex(QObject):
     dvipng to be installed on the system.
     """
 
+
     def __init__(self, cache_path):
         QObject.__init__(self)
         self.tempdir = path.join(cache_path, "latex")

runtime-pyside6/LogarithmPlotter/util/promise.py

@@ -0,0 +1,110 @@
+"""
+ *  LogarithmPlotter - 2D plotter software to make BODE plots, sequences and distribution functions.
+ *  Copyright (C) 2021-2024  Ad5001
+ *
+ *  This program is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program.  If not, see <https://www.gnu.org/licenses/>.
+"""
+from typing import Callable
+
+from PySide6.QtCore import QRunnable, Signal, QObject, Slot, QThreadPool
+from PySide6.QtQml import QJSValue
+
+from LogarithmPlotter.util.js import PyJSValue
+
+
+class InvalidReturnValue(Exception): pass
+
+
+class PyPromiseRunner(QRunnable):
+    """
+    QRunnable for running Promises in different threads.
+    """
+    def __init__(self, runner, promise):
+        QRunnable.__init__(self)
+        self.runner = runner
+        self.promise = promise
+        print("Initialized", self.runner)
+
+    def run(self):
+        try:
+            data = self.runner()
+            if isinstance(data, QObject):
+                data = data
+            elif type(data) in [int, str, float, bool, bytes]:
+                data = QJSValue(data)
+            elif data is None:
+                data = QJSValue.SpecialValue.UndefinedValue
+            elif isinstance(data, QJSValue):
+                data = data
+            elif isinstance(data, PyJSValue):
+                data = data.qjs_value
+            else:
+                raise InvalidReturnValue("Must return either a primitive, a valid QObject, JS Value, or None.")
+            self.promise.finished.emit(data)
+        except Exception as e:
+            self.promise.errored.emit(repr(e))
+
+
+class PyPromise(QObject):
+    """
+    Asynchronous Promise-like object meant to interface between Python and Javascript easily.
+    Runs to_run in another thread, and calls fulfilled (populated by then) with its return value.
+    """
+    finished = Signal((QJSValue,), (QObject,))
+    errored = Signal(Exception)
+
+    def __init__(self, to_run: Callable):
+        QObject.__init__(self)
+        self._fulfills = []
+        self._rejects = []
+        self.finished.connect(self._fulfill)
+        self.errored.connect(self._reject)
+        self._runner = PyPromiseRunner(to_run, self)
+        QThreadPool.globalInstance().start(self._runner)
+
+
+    @Slot(QJSValue, result=QObject)
+    @Slot(QJSValue, QJSValue, result=QObject)
+    def then(self, on_fulfill: QJSValue | Callable, on_reject: QJSValue | Callable = None):
+        """
+        Adds listeners for both fulfilment and catching errors of the Promise.
+        """
+        if isinstance(on_fulfill, QJSValue):
+            self._fulfills.append(PyJSValue(on_fulfill))
+        elif isinstance(on_fulfill, Callable):
+            self._fulfills.append(on_fulfill)
+        if isinstance(on_reject, QJSValue):
+            self._rejects.append(PyJSValue(on_reject))
+        elif isinstance(on_reject, Callable):
+            self._rejects.append(on_reject)
+
+    @Slot(QJSValue)
+    @Slot(QObject)
+    def _fulfill(self, data):
+        no_return = [None, QJSValue.SpecialValue.UndefinedValue]
+        for on_fulfill in self._fulfills:
+            try:
+                result = on_fulfill(data)
+                data = result if result not in no_return else data  # Forward data.
+            except Exception as e:
+                self._reject(repr(e))
+                break
+
+    @Slot(QJSValue)
+    @Slot(str)
+    def _reject(self, error):
+        no_return = [None, QJSValue.SpecialValue.UndefinedValue]
+        for on_reject in self._rejects:
+            result = on_reject(error)
+            error = result if result not in no_return else error  # Forward data.