🚧 dinglehopper: WIP data structure for extracted text

extracted_text.py

@@ -0,0 +1,42 @@
+import attr
+
+
+@attr.s(frozen=True)
+class ExtractedText:
+    segments = attr.ib()
+    joiner = attr.ib(type=str)
+    # XXX Use type annotations for attr types when support for Python 3.5 is dropped
+    # XXX Also I think these are not validated?
+
+    @property
+    def text(self):
+        return self.joiner.join(s.text for s in self.segments)
+
+    def segment_id_for_pos(self, pos):
+        i = 0
+        for s in self.segments:
+            if i <= pos < i + len(s.text):
+                return s.id
+            i += len(s.text)
+            if i <= pos < i + len(self.joiner):
+                return None
+            i += len(self.joiner)
+
+
+@attr.s(frozen=True)
+class ExtractedTextSegment:
+    id = attr.ib(type=str)
+    text = attr.ib(type=str)
+
+
+test1 = ExtractedText([
+    ExtractedTextSegment('s0', 'foo'),
+    ExtractedTextSegment('s1', 'bar'),
+    ExtractedTextSegment('s2', 'bazinga')
+], ' ')
+
+
+assert test1.text == 'foo bar bazinga'
+assert test1.segment_id_for_pos(0) == 's0'
+assert test1.segment_id_for_pos(3) == None
+assert test1.segment_id_for_pos(10) == 's2'