From d73d271a4fdd163a564772ff5fa31198c2a6ab08 Mon Sep 17 00:00:00 2001
From: Don Cross <cosinekitty@gmail.com>
Date: Mon, 13 Feb 2023 13:19:13 -0500
Subject: [PATCH] Fixed pydown to understand imported symbols.

In order to import typing.Union into the module namespace,
I had to fix pydown to recognize Union as a defined symbol.
---
 demo/python/astronomy.py             |  3 ++-
 generate/pydown/pydown.py            | 12 ++++++++++++
 generate/template/astronomy.py       |  3 ++-
 source/python/astronomy/astronomy.py |  3 ++-
 4 files changed, 18 insertions(+), 3 deletions(-)

diff --git a/demo/python/astronomy.py b/demo/python/astronomy.py
index 74bdd703..fbd1003d 100644
--- a/demo/python/astronomy.py
+++ b/demo/python/astronomy.py
@@ -36,6 +36,7 @@ import datetime
 import enum
 import re
 import abc
+from typing import Union
 
 def _cbrt(x):
     if x < 0.0:
@@ -728,7 +729,7 @@ class Time:
         such as the orbits of planets around the Sun, or the Moon around the Earth.
         Historically, Terrestrial Time has also been known by the term *Ephemeris Time* (ET).
     """
-    def __init__(self, ut, tt = None):
+    def __init__(self, ut : Union[float, str], tt = None):
         if isinstance(ut, str):
             # Undocumented hack, to make repr(time) reversible.
             other = Time.Parse(ut)
diff --git a/generate/pydown/pydown.py b/generate/pydown/pydown.py
index dc1e5fda..89c7a63a 100755
--- a/generate/pydown/pydown.py
+++ b/generate/pydown/pydown.py
@@ -362,6 +362,17 @@ def ConstantsMd(inPythonFileName):
     clist = []
     with open(inPythonFileName) as infile:
         for line in infile:
+            # Consider symbols like Union defined in lines like the following:
+            # "from typing import Union"
+            tokens = line.split()
+            if len(tokens) > 3 and tokens[0] == 'from' and tokens[2] == 'import':
+                for name in tokens[3:]:
+                    if name != ',':
+                        documentedSymbolSet.add(name)
+                continue
+
+            # Consider symbols like KM_PER_AU defined in lines like the following:
+            # "KM_PER_AU = 1.4959787069098932e+8   #<const> The number of kilometers per astronomical unit."
             parts = line.split('#<const>')
             if len(parts) == 2:
                 code = parts[0].strip()
@@ -373,6 +384,7 @@ def ConstantsMd(inPythonFileName):
                     symbol = tokens[0]
                     clist.append((symbol, codeText, doc))
                     documentedSymbolSet.add(symbol)
+                    continue
 
     for (symbol, code, doc) in sorted(clist):
         md += '\n---\n\n'
diff --git a/generate/template/astronomy.py b/generate/template/astronomy.py
index 9442de7a..58589156 100644
--- a/generate/template/astronomy.py
+++ b/generate/template/astronomy.py
@@ -36,6 +36,7 @@ import datetime
 import enum
 import re
 import abc
+from typing import Union
 
 def _cbrt(x):
     if x < 0.0:
@@ -728,7 +729,7 @@ class Time:
         such as the orbits of planets around the Sun, or the Moon around the Earth.
         Historically, Terrestrial Time has also been known by the term *Ephemeris Time* (ET).
     """
-    def __init__(self, ut, tt = None):
+    def __init__(self, ut : Union[float, str], tt = None):
         if isinstance(ut, str):
             # Undocumented hack, to make repr(time) reversible.
             other = Time.Parse(ut)
diff --git a/source/python/astronomy/astronomy.py b/source/python/astronomy/astronomy.py
index 74bdd703..fbd1003d 100644
--- a/source/python/astronomy/astronomy.py
+++ b/source/python/astronomy/astronomy.py
@@ -36,6 +36,7 @@ import datetime
 import enum
 import re
 import abc
+from typing import Union
 
 def _cbrt(x):
     if x < 0.0:
@@ -728,7 +729,7 @@ class Time:
         such as the orbits of planets around the Sun, or the Moon around the Earth.
         Historically, Terrestrial Time has also been known by the term *Ephemeris Time* (ET).
     """
-    def __init__(self, ut, tt = None):
+    def __init__(self, ut : Union[float, str], tt = None):
         if isinstance(ut, str):
             # Undocumented hack, to make repr(time) reversible.
             other = Time.Parse(ut)