Add byte and short converters utilizing hints

And test them, to improve confidence that conversion hints work.

Author: ctrueden

src/scyjava/_convert.py

@@ -163,15 +163,33 @@ def _stock_java_converters() -> List[Converter]:
             predicate=lambda obj: isinstance(obj, bool),
             converter=_jc.Boolean,
         ),
+        # int -> java.lang.Byte
+        Converter(
+            predicate=lambda obj, **hints: isinstance(obj, int)
+            and ("type" in hints and hints["type"] in ("b", "byte", "Byte"))
+            and _jc.Byte.MIN_VALUE <= obj <= _jc.Byte.MAX_VALUE,
+            converter=_jc.Byte,
+            priority=Priority.HIGH,
+        ),
+        # int -> java.lang.Short
+        Converter(
+            predicate=lambda obj, **hints: isinstance(obj, int)
+            and ("type" in hints and hints["type"] in ("s", "short", "Short"))
+            and _jc.Short.MIN_VALUE <= obj <= _jc.Short.MAX_VALUE,
+            converter=_jc.Short,
+            priority=Priority.HIGH,
+        ),
         # int -> java.lang.Integer
         Converter(
-            predicate=lambda obj: isinstance(obj, int)
+            predicate=lambda obj, **hints: isinstance(obj, int)
+            and ("type" not in hints or hints["type"] in ("i", "int", "Integer"))
             and _jc.Integer.MIN_VALUE <= obj <= _jc.Integer.MAX_VALUE,
             converter=_jc.Integer,
         ),
         # int -> java.lang.Long
         Converter(
-            predicate=lambda obj: isinstance(obj, int)
+            predicate=lambda obj, **hints: isinstance(obj, int)
+            and ("type" not in hints or hints["type"] in ("j", "l", "long", "Long"))
             and _jc.Long.MIN_VALUE <= obj <= _jc.Long.MAX_VALUE,
             converter=_jc.Long,
             priority=Priority.NORMAL - 1,
@@ -184,7 +202,8 @@ def _stock_java_converters() -> List[Converter]:
         ),
         # float -> java.lang.Float
         Converter(
-            predicate=lambda obj: isinstance(obj, float)
+            predicate=lambda obj, **hints: isinstance(obj, float)
+            and ("type" not in hints or hints["type"] in ("f", "float", "Float"))
             and (
                 math.isinf(obj)
                 or math.isnan(obj)
@@ -194,7 +213,8 @@ def _stock_java_converters() -> List[Converter]:
         ),
         # float -> java.lang.Double
         Converter(
-            predicate=lambda obj: isinstance(obj, float)
+            predicate=lambda obj, **hints: isinstance(obj, float)
+            and ("type" not in hints or hints["type"] in ("d", "double", "Double"))
             and (
                 math.isinf(obj)
                 or math.isnan(obj)

tests/test_convert.py

@@ -2,8 +2,6 @@
 from os import getcwd
 from pathlib import Path
 
-from jpype import JByte
-
 from scyjava import (
     Converter,
     config,
@@ -60,13 +58,22 @@ def testBoolean(self):
         assert pfalse is False
 
     def testByte(self):
-        # NB we can't (yet) convert TO Bytes, since there is not (yet)
-        # a great type to convert FROM. We convert python ints to Integers
-        i = 5
-        ji = JByte(i)
-        pi = to_python(ji)
-        assert i == pi
-        assert str(i) == str(pi)
+        obyte = 5
+        jbyte = to_java(obyte, type="b")
+        assert jinstance(jbyte, "java.lang.Byte")
+        assert obyte == jbyte.byteValue()
+        pbyte = to_python(jbyte)
+        assert isinstance(pbyte, int)
+        assert obyte == pbyte
+
+    def testShort(self):
+        oshort = 5
+        jshort = to_java(oshort, type="s")
+        assert jinstance(jshort, "java.lang.Short")
+        assert oshort == jshort.shortValue()
+        pshort = to_python(jshort)
+        assert isinstance(pshort, int)
+        assert oshort == pshort
 
     def testInteger(self):
         oint = 5