Improve email ingestion: handle inline replies and track quoted content attribution

CODEOWNERS

@@ -0,0 +1 @@
+* @gvanrossum @gvanrossum-ms @umeshma @robgruen

test/test_email_import.py

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+# Copyright (c) Microsoft Corporation.
+# Licensed under the MIT License.
+
+from typeagent.emails.email_import import (
+    is_inline_reply,
+    parse_email_chunks,
+)
+
+
+class TestIsInlineReply:
+    def test_empty_text(self) -> None:
+        assert is_inline_reply("") is False
+
+    def test_no_header(self) -> None:
+        text = "Just a regular email with no quoted content."
+        assert is_inline_reply(text) is False
+
+    def test_top_posted_reply(self) -> None:
+        # This has "On ... wrote:" but all quotes are at the bottom, no interleaving
+        text = """\
+Thanks for the info!
+
+On Mon, Dec 10, 2020 at 10:30 AM Someone wrote:
+
+> Here is some quoted text.
+> More quoted text.
+> Even more.
+"""
+        assert is_inline_reply(text) is False
+
+    def test_inline_reply(self) -> None:
+        text = """\
+I've given my replies in line with the quoted text.
+
+On Mon, Dec 10, 2020 at 10:30 AM Someone wrote:
+> Quoted blah.
+
+That is clearly BS.
+
+> Quoted blah blah.
+
+Here I must agree.
+
+> More quoted text.
+
+-- 
+Guido van Rossum
+"""
+        assert is_inline_reply(text) is True
+
+    def test_inline_reply_no_preamble(self) -> None:
+        text = """\
+On Mon, Dec 10, 2020 at 10:30 AM Someone wrote:
+> First quote.
+
+My first response.
+
+> Second quote.
+
+My second response.
+"""
+        assert is_inline_reply(text) is True
+
+
+class TestParseEmailChunks:
+    def test_empty_text(self) -> None:
+        assert parse_email_chunks("") == []
+
+    def test_no_inline_pattern(self) -> None:
+        text = "Just a regular email."
+        result = parse_email_chunks(text)
+        assert len(result) == 1
+        assert result[0] == ("Just a regular email.", None)
+
+    def test_basic_inline_reply(self) -> None:
+        text = """\
+I've given my replies in line with the quoted text.
+
+On Mon, Dec 10, 2020 at 10:30 AM Someone wrote:
+> Quoted blah.
+
+That is clearly BS.
+
+> Quoted blah blah.
+
+Here I must agree.
+
+> More quoted text.
+
+-- 
+Guido van Rossum
+"""
+        result = parse_email_chunks(text)
+        # Should have: preamble (original), quoted, reply, quoted, reply, quoted
+        texts = [chunk[0] for chunk in result]
+        sources = [chunk[1] for chunk in result]
+
+        # Check we have all the content
+        assert any("I've given my replies" in t for t in texts)
+        assert any("That is clearly BS" in t for t in texts)
+        assert any("Here I must agree" in t for t in texts)
+        assert any("Quoted blah" in t for t in texts)
+
+        # Original content should have None source
+        for text, source in result:
+            if "I've given my replies" in text or "That is clearly BS" in text:
+                assert source is None
+
+        # Quoted content should have the person's name
+        for text, source in result:
+            if "Quoted blah" in text:
+                assert source == "Someone"
+
+        # Signature should NOT be included
+        assert not any("Guido van Rossum" in t for t in texts)
+
+    def test_extracts_quoted_person_name(self) -> None:
+        text = """\
+On Mon, Dec 10, 2020 at 10:30 AM John Doe wrote:
+> Is Python good?
+
+Yes, absolutely!
+
+> What about JavaScript?
+
+It has its uses.
+"""
+        result = parse_email_chunks(text)
+
+        # Find quoted chunks - they should have "John Doe" as source
+        quoted_chunks = [(t, s) for t, s in result if s is not None]
+        assert len(quoted_chunks) == 2
+        for text, source in quoted_chunks:
+            assert source == "John Doe"
+
+    def test_preserves_preamble(self) -> None:
+        text = """\
+Here's my preamble before the inline replies.
+
+On Mon, Dec 10, 2020 at 10:30 AM Someone wrote:
+> Question?
+
+Answer!
+"""
+        result = parse_email_chunks(text)
+        texts = [chunk[0] for chunk in result]
+
+        assert any("preamble" in t for t in texts)
+        assert any("Answer" in t for t in texts)
+
+    def test_strips_trailing_delimiters(self) -> None:
+        text = """\
+On Mon, Dec 10, 2020 at 10:30 AM Someone wrote:
+> Question?
+
+Answer!
+_______________
+"""
+        result = parse_email_chunks(text)
+        # Last non-quoted chunk should not end with underscores
+        original_chunks = [t for t, s in result if s is None]
+        assert len(original_chunks) > 0
+        assert not original_chunks[-1].endswith("_")
+
+    def test_quoted_content_is_unabbreviated(self) -> None:
+        text = """\
+On Mon, Dec 10, 2020 at 10:30 AM Someone wrote:
+> This is a very long quoted line that should be preserved in full.
+> And this is another line that continues the quote.
+> Even more content here.
+
+My response.
+"""
+        result = parse_email_chunks(text)
+
+        # Find the quoted chunk
+        quoted = [t for t, s in result if s is not None]
+        assert len(quoted) == 1
+        # Full content should be preserved
+        assert "very long quoted line" in quoted[0]
+        assert "another line" in quoted[0]
+        assert "Even more content" in quoted[0]