space_sep=bool <- sep=string, and adapt tests

afvincent · afvincent · commit 3049a2d90b00 · 2017-08-25T09:39:45.000-07:00
diff --git a/lib/matplotlib/tests/test_ticker.py b/lib/matplotlib/tests/test_ticker.py
@@ -585,7 +585,7 @@ def test_params(self, input, expected):
         UNIT = u's'  # seconds
         DIGITS = u'0123456789'  # %timeit showed 10-20% faster search than set
 
-        # Case 0: unit='' (default) and space_sep=True (default).
+        # Case 0: unit='' (default) and sep=' ' (default).
         # 'expected' already corresponds to this reference case.
         exp_outputs = (_s for _s in expected)  # simple copy of 'expected'
         formatters = (
@@ -596,7 +596,7 @@ def test_params(self, input, expected):
         for _formatter, _exp_output in zip(formatters, exp_outputs):
             assert _formatter(input) == _exp_output
 
-        # Case 1: unit=UNIT and space_sep=True (default).
+        # Case 1: unit=UNIT and sep=' ' (default).
         # Append a unit symbol to the reference case.
         # Beware of the values in [1, 1000), where there is no prefix!
         exp_outputs = (_s + u" " + UNIT if _s[-1] in DIGITS  # case w/o prefix
@@ -609,28 +609,34 @@ def test_params(self, input, expected):
         for _formatter, _exp_output in zip(formatters, exp_outputs):
             assert _formatter(input) == _exp_output
 
-        # Case 2: unit=UNIT and space_sep=False.
-        # Remove the space separator from the reference case.
-        exp_outputs = (_s.replace(" ", "") + UNIT for _s in expected)
-        formatters = (
-            mticker.EngFormatter(unit=UNIT, space_sep=False),  # places=None
-            mticker.EngFormatter(unit=UNIT, places=0, space_sep=False),
-            mticker.EngFormatter(unit=UNIT, places=2, space_sep=False)
-        )
-        for _formatter, _exp_output in zip(formatters, exp_outputs):
-            assert _formatter(input) == _exp_output
-
-        # Case 3: unit='' (default) and space_sep=False.
-        # Remove the space separator from the reference case and append
-        # a unit symbol to it.
-        exp_outputs = (_s.replace(" ", "") for _s in expected)
-        formatters = (
-            mticker.EngFormatter(space_sep=False),  # places=None (default)
-            mticker.EngFormatter(places=0, space_sep=False),
-            mticker.EngFormatter(places=2, space_sep=False)
-        )
-        for _formatter, _exp_output in zip(formatters, exp_outputs):
-            assert _formatter(input) == _exp_output
+        # Test several non default separators: no separator, a narrow
+        # no-break space (unicode character) and an extravagant string.
+        for _sep in ("","\u202f", "@_@"):
+            # Case 2x: unit=UNIT and sep=_sep.
+            # Remove the space separator from the reference case.
+            exp_outputs = (_s + _sep + UNIT if _s[-1] in DIGITS  # no prefix
+                           else _s.replace(" ", _sep) + UNIT
+                           for _s in expected)
+            #exp_outputs = list(_s.replace(" ", _sep) + UNIT for _s in expected)
+            formatters = (
+                mticker.EngFormatter(unit=UNIT, sep=_sep),  # places=None
+                mticker.EngFormatter(unit=UNIT, places=0, sep=_sep),
+                mticker.EngFormatter(unit=UNIT, places=2, sep=_sep)
+            )
+            for _formatter, _exp_output in zip(formatters, exp_outputs):
+                assert _formatter(input) == _exp_output
+
+            # Case 3x: unit='' (default) and sep=_sep.
+            # Remove the space separator from the reference case and append
+            # a unit symbol to it.
+            exp_outputs = (_s.replace(" ", _sep) for _s in expected)
+            formatters = (
+                mticker.EngFormatter(sep=_sep),  # places=None (default)
+                mticker.EngFormatter(places=0, sep=_sep),
+                mticker.EngFormatter(places=2, sep=_sep)
+            )
+            for _formatter, _exp_output in zip(formatters, exp_outputs):
+                assert _formatter(input) == _exp_output
 
 
 class TestPercentFormatter(object):
diff --git a/lib/matplotlib/ticker.py b/lib/matplotlib/ticker.py
@@ -1193,8 +1193,9 @@ class EngFormatter(Formatter):
     specified in digits after the decimal point (there will be between
     one and three digits before the decimal point).
 
-    `space_sep` controls if there is a space between the number and the
-    prefix/unit. For example, '3.14 mV' if True and '3.14mV' if False.
+    `sep` is the separator (a string) that is used between the number
+    and the prefix/unit. For example, '3.14 mV' if `sep` is " " (default)
+    and '3.14mV' if `sep` is "".
     """
     # The SI engineering prefixes
     ENG_PREFIXES = {
@@ -1217,32 +1218,32 @@ class EngFormatter(Formatter):
          24: "Y"
     }
 
-    def __init__(self, unit="", places=None, space_sep=True):
+    def __init__(self, unit="", places=None, sep=" "):
         """
         Parameters
         ----------
-        unit: str (default: u"")
+        unit: string (default: "")
             Unit symbol to use.
 
         places: int (default: None)
             Precision, i.e. number of digits after the decimal point.
             If it is None, falls back to the floating point format '%g'.
 
-        space_sep: boolean (default: True)
-            If True, a (single) space is used between the value and the
-            prefix/unit, else the prefix/unit is directly appended to the
-            value.
+        sep: string (default: " ")
+            String used between the value and the prefix/unit. Beside the
+            default behavior, some other useful use cases may be:
+                * sep="" to append directly the prefix/unit to the value;
+                * sep="\u00a0" to use a no-break space;
+                * sep="\u202f" to use a narrow no-break space.
         """
         self.unit = unit
         self.places = places
-        if space_sep is True:
-            self.sep = u" "  # 1 space
-        else:
-            self.sep = u""  # no space
+        self.sep = sep
 
     def __call__(self, x, pos=None):
         s = "%s%s" % (self.format_eng(x), self.unit)
-        s = s.strip()  # Remove separator when there is neither prefix nor unit
+        # Remove the trailing separator when there is neither prefix nor unit
+        s = s.strip(self.sep)
         return self.fix_minus(s)
 
     def format_eng(self, num):
