Quoth Ramakrishnan Muthukrishnan on Aug 05 at 11:35 pm: > Ramakrishnan Muthukrishnan <ram at rkrishnan.org> writes: > > > Hi, > > > > Pardon me for using non-standard terms here because of lack of knowledge > > of the language used in the email world. > > > > I have this thread in which some messages are tagged unread. When the > > thread is opened, I see that those unread messages are not shown in full > > in the threaded view. Instead they appear `folded' with only the summary > > appearing in the thread, as if they are read. > > > > Here is a screenshot: http://i.imgur.com/Eh8SKe6.png > > > > I am attaching the messages in the thread shown in the screenshot as a > > tar.bz2 file. > > I just forgot to mention that I see this only when I do a > notmuch-search with `*' and not when I search with a tag.
'*' turns out to be the key. When showing a thread, notmuch-show-build-buffer constructs a new query from the thread ID and the original search query of the form thread:X and (original query) If the original query is '*', this is thread:X and (*) But * isn't part of the Xapian query syntax. Notmuch specially handles queries that exactly match "*" before passing the query to Xapian. When * is embedded in a larger query, this special casing doesn't apply. In fact, Xapian parses this query as (Tmail AND (and:(pos=1) FILTER GX)) The "and" in the query turned into a plain search term (the "AND" is a proper boolean operator, but is unrelated to the provided query). This is a symptom of a general problem where we assume queries are textually composable, when they are not. We have the same problem at least in notmuch-search-filter and in notmuch tag query optimization. In this particular case, the * causes Xapian's query grammar to fail to parse the query, which Xapian handles by re-parsing the entire query will all query features disabled (which includes disabling support for boolean operators). Unfortunately, just handling * better isn't really a solution because it's just one of many things that violates query composability. Some solutions I can see are: 1) Switch to a composable query syntax (which would include *). This, obviously, requires a custom query parser, but is the most localized change I can think of and keeps queries as strings. 2) Never construct queries by pasting strings together. This would require changes to both the libnotmuch and CLI interfaces and queries could no longer be strings, but in the words of Alan Perlis, the string is a stark data structure. (In the case of show, I would actually love it if we could specify separate search and match queries because that would eliminate --entire-thread as well as the fallback in notmuch-show-build-buffer when search returns nothing, but I digress.) 3) Keep queries as plain strings, but switch to some hybrid syntax that lets us combine Xapian queries with composable operators parsed by notmuch. When we need to combine queries, do it using the composable operators. This actually may not be a bad way to transition to a full custom query parser; I think it would be relatively easy to take over parsing Xapian's boolean syntax, but leave the "prob" parsing to Xapian. I lean towards 3 because it seems like the least disruptive and offers a smooth transition to 1.