Preserve whitespace in svg output.

anntzer · anntzer · commit 5c5432454915 · 2019-03-15T10:29:00.000+01:00
See https://www.w3.org/TR/css-text-3/#white-space-property, which replaces the deprecated https://developer.mozilla.org/en-US/docs/Web/SVG/Attribute/xml:space (which wasn't used before either).
diff --git a/lib/matplotlib/backends/backend_svg.py b/lib/matplotlib/backends/backend_svg.py
@@ -318,7 +318,9 @@ def _write_default_style(self):
         writer = self.writer
         default_style = generate_css({
             'stroke-linejoin': 'round',
-            'stroke-linecap': 'butt'})
+            'stroke-linecap': 'butt',
+            'white-space': 'pre',
+        })
         writer.start('defs')
         writer.start('style', type='text/css')
         writer.data('*{%s}\n' % default_style)
diff --git a/lib/matplotlib/tests/baseline_images/test_backend_svg/white_space_pre.svg b/lib/matplotlib/tests/baseline_images/test_backend_svg/white_space_pre.svg
@@ -0,0 +1,24 @@
+<?xml version="1.0" encoding="utf-8" standalone="no"?>
+<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN"
+  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
+<!-- Created with matplotlib (https://matplotlib.org/) -->
+<svg height="432pt" version="1.1" viewBox="0 0 576 432" width="576pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
+ <defs>
+  <style type="text/css">
+*{stroke-linecap:butt;stroke-linejoin:round;white-space:pre;}
+  </style>
+ </defs>
+ <g id="figure_1">
+  <g id="patch_1">
+   <path d="M 0 432 
+L 576 432 
+L 576 0 
+L 0 0 
+z
+" style="fill:#ffffff;"/>
+  </g>
+  <g id="text_1">
+   <text style="font-family:DejaVu Sans;font-size:12px;font-style:normal;font-weight:normal;text-anchor:start;" transform="rotate(-0, 288, 216)" x="288" y="216">a b   c</text>
+  </g>
+ </g>
+</svg>
diff --git a/lib/matplotlib/tests/test_backend_svg.py b/lib/matplotlib/tests/test_backend_svg.py
@@ -76,6 +76,13 @@ def test_text_urls():
     assert expected in buf
 
 
+@image_comparison(baseline_images=['white_space_pre'], extensions=['svg'])
+def test_white_space_pre():
+    plt.rcParams["svg.fonttype"] = "none"
+    fig = plt.figure()
+    fig.text(.5, .5, "a b   c")
+
+
 @image_comparison(baseline_images=['bold_font_output'], extensions=['svg'])
 def test_bold_font_output():
     fig = plt.figure()
