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</pre><pre class="rust"><code><span class="kw">use </span>std::io;
<span class="kw">use </span>std::iter::Sum;
<span class="kw">use </span>std::ops::{AddAssign, Range};
<span class="kw">use </span>std::sync::atomic::{AtomicUsize, Ordering};
<span class="kw">use </span>std::sync::{Arc, Mutex};
<span class="kw">use </span>common::{BinarySerializable, HasLen};
<span class="kw">use </span>lru::LruCache;
<span class="kw">use </span>ownedbytes::OwnedBytes;
<span class="kw">use </span><span class="kw">super</span>::footer::DocStoreFooter;
<span class="kw">use </span><span class="kw">super</span>::index::SkipIndex;
<span class="kw">use </span><span class="kw">super</span>::Decompressor;
<span class="kw">use </span><span class="kw">crate</span>::directory::FileSlice;
<span class="kw">use </span><span class="kw">crate</span>::error::DataCorruption;
<span class="kw">use </span><span class="kw">crate</span>::fastfield::AliveBitSet;
<span class="kw">use </span><span class="kw">crate</span>::schema::Document;
<span class="kw">use </span><span class="kw">crate</span>::space_usage::StoreSpaceUsage;
<span class="kw">use </span><span class="kw">crate</span>::store::index::Checkpoint;
<span class="kw">use </span><span class="kw">crate</span>::DocId;
<span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">const </span>DOCSTORE_CACHE_CAPACITY: usize = <span class="number">100</span>;
<span class="kw">type </span>Block = OwnedBytes;
<span class="doccomment">/// Reads document off tantivy&#39;s [`Store`](./index.html)
</span><span class="kw">pub struct </span>StoreReader {
decompressor: Decompressor,
data: FileSlice,
skip_index: Arc&lt;SkipIndex&gt;,
space_usage: StoreSpaceUsage,
cache: BlockCache,
}
<span class="doccomment">/// The cache for decompressed blocks.
</span><span class="kw">struct </span>BlockCache {
cache: Mutex&lt;LruCache&lt;usize, Block&gt;&gt;,
cache_hits: Arc&lt;AtomicUsize&gt;,
cache_misses: Arc&lt;AtomicUsize&gt;,
}
<span class="kw">impl </span>BlockCache {
<span class="kw">fn </span>get_from_cache(<span class="kw-2">&amp;</span><span class="self">self</span>, pos: usize) -&gt; <span class="prelude-ty">Option</span>&lt;Block&gt; {
<span class="kw">if let </span><span class="prelude-val">Some</span>(block) = <span class="self">self</span>.cache.lock().unwrap().get(<span class="kw-2">&amp;</span>pos) {
<span class="self">self</span>.cache_hits.fetch_add(<span class="number">1</span>, Ordering::SeqCst);
<span class="kw">return </span><span class="prelude-val">Some</span>(block.clone());
}
<span class="self">self</span>.cache_misses.fetch_add(<span class="number">1</span>, Ordering::SeqCst);
<span class="prelude-val">None
</span>}
<span class="kw">fn </span>put_into_cache(<span class="kw-2">&amp;</span><span class="self">self</span>, pos: usize, data: Block) {
<span class="self">self</span>.cache.lock().unwrap().put(pos, data);
}
<span class="kw">fn </span>stats(<span class="kw-2">&amp;</span><span class="self">self</span>) -&gt; CacheStats {
CacheStats {
cache_hits: <span class="self">self</span>.cache_hits.load(Ordering::Relaxed),
cache_misses: <span class="self">self</span>.cache_misses.load(Ordering::Relaxed),
num_entries: <span class="self">self</span>.len(),
}
}
<span class="kw">fn </span>len(<span class="kw-2">&amp;</span><span class="self">self</span>) -&gt; usize {
<span class="self">self</span>.cache.lock().unwrap().len()
}
<span class="attribute">#[cfg(test)]
</span><span class="kw">fn </span>peek_lru(<span class="kw-2">&amp;</span><span class="self">self</span>) -&gt; <span class="prelude-ty">Option</span>&lt;usize&gt; {
<span class="self">self</span>.cache
.lock()
.unwrap()
.peek_lru()
.map(|(<span class="kw-2">&amp;</span>k, <span class="kw">_</span>)| k <span class="kw">as </span>usize)
}
}
<span class="attribute">#[derive(Debug, Default)]
</span><span class="doccomment">/// CacheStats for the `StoreReader`.
</span><span class="kw">pub struct </span>CacheStats {
<span class="doccomment">/// The number of entries in the cache
</span><span class="kw">pub </span>num_entries: usize,
<span class="doccomment">/// The number of cache hits.
</span><span class="kw">pub </span>cache_hits: usize,
<span class="doccomment">/// The number of cache misses.
</span><span class="kw">pub </span>cache_misses: usize,
}
<span class="kw">impl </span>AddAssign <span class="kw">for </span>CacheStats {
<span class="kw">fn </span>add_assign(<span class="kw-2">&amp;mut </span><span class="self">self</span>, other: <span class="self">Self</span>) {
<span class="kw-2">*</span><span class="self">self </span>= <span class="self">Self </span>{
num_entries: <span class="self">self</span>.num_entries + other.num_entries,
cache_hits: <span class="self">self</span>.cache_hits + other.cache_hits,
cache_misses: <span class="self">self</span>.cache_misses + other.cache_misses,
};
}
}
<span class="kw">impl </span>Sum <span class="kw">for </span>CacheStats {
<span class="kw">fn </span>sum&lt;I: Iterator&lt;Item = <span class="self">Self</span>&gt;&gt;(<span class="kw-2">mut </span>iter: I) -&gt; <span class="self">Self </span>{
<span class="kw">let </span><span class="kw-2">mut </span>first = iter.next().unwrap_or_default();
<span class="kw">for </span>el <span class="kw">in </span>iter {
first += el;
}
first
}
}
<span class="kw">impl </span>StoreReader {
<span class="doccomment">/// Opens a store reader
</span><span class="kw">pub fn </span>open(store_file: FileSlice, cache_size: usize) -&gt; io::Result&lt;StoreReader&gt; {
<span class="kw">let </span>(footer, data_and_offset) = DocStoreFooter::extract_footer(store_file)<span class="question-mark">?</span>;
<span class="kw">let </span>(data_file, offset_index_file) = data_and_offset.split(footer.offset <span class="kw">as </span>usize);
<span class="kw">let </span>index_data = offset_index_file.read_bytes()<span class="question-mark">?</span>;
<span class="kw">let </span>space_usage = StoreSpaceUsage::new(data_file.len(), offset_index_file.len());
<span class="kw">let </span>skip_index = SkipIndex::open(index_data);
<span class="prelude-val">Ok</span>(StoreReader {
decompressor: footer.decompressor,
data: data_file,
cache: BlockCache {
cache: Mutex::new(LruCache::new(cache_size)),
cache_hits: Default::default(),
cache_misses: Default::default(),
},
skip_index: Arc::new(skip_index),
space_usage,
})
}
<span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>block_checkpoints(<span class="kw-2">&amp;</span><span class="self">self</span>) -&gt; <span class="kw">impl </span>Iterator&lt;Item = Checkpoint&gt; + <span class="lifetime">&#39;_ </span>{
<span class="self">self</span>.skip_index.checkpoints()
}
<span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>decompressor(<span class="kw-2">&amp;</span><span class="self">self</span>) -&gt; Decompressor {
<span class="self">self</span>.decompressor
}
<span class="doccomment">/// Returns the cache hit and miss statistics of the store reader.
</span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>cache_stats(<span class="kw-2">&amp;</span><span class="self">self</span>) -&gt; CacheStats {
<span class="self">self</span>.cache.stats()
}
<span class="doccomment">/// Get checkpoint for `DocId`. The checkpoint can be used to load a block containing the
/// document.
///
/// Advanced API. In most cases use [`get`](Self::get).
</span><span class="kw">fn </span>block_checkpoint(<span class="kw-2">&amp;</span><span class="self">self</span>, doc_id: DocId) -&gt; <span class="kw">crate</span>::Result&lt;Checkpoint&gt; {
<span class="self">self</span>.skip_index.seek(doc_id).ok_or_else(|| {
<span class="kw">crate</span>::TantivyError::InvalidArgument(<span class="macro">format!</span>(<span class="string">&quot;Failed to lookup Doc #{}.&quot;</span>, doc_id))
})
}
<span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>block_data(<span class="kw-2">&amp;</span><span class="self">self</span>) -&gt; io::Result&lt;OwnedBytes&gt; {
<span class="self">self</span>.data.read_bytes()
}
<span class="kw">fn </span>get_compressed_block(<span class="kw-2">&amp;</span><span class="self">self</span>, checkpoint: <span class="kw-2">&amp;</span>Checkpoint) -&gt; io::Result&lt;OwnedBytes&gt; {
<span class="self">self</span>.data.slice(checkpoint.byte_range.clone()).read_bytes()
}
<span class="doccomment">/// Loads and decompresses a block.
///
/// Advanced API. In most cases use [`get`](Self::get).
</span><span class="kw">fn </span>read_block(<span class="kw-2">&amp;</span><span class="self">self</span>, checkpoint: <span class="kw-2">&amp;</span>Checkpoint) -&gt; io::Result&lt;Block&gt; {
<span class="kw">let </span>cache_key = checkpoint.byte_range.start;
<span class="kw">if let </span><span class="prelude-val">Some</span>(block) = <span class="self">self</span>.cache.get_from_cache(cache_key) {
<span class="kw">return </span><span class="prelude-val">Ok</span>(block);
}
<span class="kw">let </span>compressed_block = <span class="self">self</span>.get_compressed_block(checkpoint)<span class="question-mark">?</span>;
<span class="kw">let </span>decompressed_block =
OwnedBytes::new(<span class="self">self</span>.decompressor.decompress(compressed_block.as_ref())<span class="question-mark">?</span>);
<span class="self">self</span>.cache
.put_into_cache(cache_key, decompressed_block.clone());
<span class="prelude-val">Ok</span>(decompressed_block)
}
<span class="doccomment">/// Reads a given document.
///
/// Calling `.get(doc)` is relatively costly as it requires
/// decompressing a compressed block. The store utilizes a LRU cache,
/// so accessing docs from the same compressed block should be faster.
/// For that reason a store reader should be kept and reused.
///
/// It should not be called to score documents
/// for instance.
</span><span class="kw">pub fn </span>get(<span class="kw-2">&amp;</span><span class="self">self</span>, doc_id: DocId) -&gt; <span class="kw">crate</span>::Result&lt;Document&gt; {
<span class="kw">let </span><span class="kw-2">mut </span>doc_bytes = <span class="self">self</span>.get_document_bytes(doc_id)<span class="question-mark">?</span>;
<span class="prelude-val">Ok</span>(Document::deserialize(<span class="kw-2">&amp;mut </span>doc_bytes)<span class="question-mark">?</span>)
}
<span class="doccomment">/// Returns raw bytes of a given document.
///
/// Calling `.get(doc)` is relatively costly as it requires
/// decompressing a compressed block. The store utilizes a LRU cache,
/// so accessing docs from the same compressed block should be faster.
/// For that reason a store reader should be kept and reused.
</span><span class="kw">pub fn </span>get_document_bytes(<span class="kw-2">&amp;</span><span class="self">self</span>, doc_id: DocId) -&gt; <span class="kw">crate</span>::Result&lt;OwnedBytes&gt; {
<span class="kw">let </span>checkpoint = <span class="self">self</span>.block_checkpoint(doc_id)<span class="question-mark">?</span>;
<span class="kw">let </span>block = <span class="self">self</span>.read_block(<span class="kw-2">&amp;</span>checkpoint)<span class="question-mark">?</span>;
<span class="self">Self</span>::get_document_bytes_from_block(block, doc_id, <span class="kw-2">&amp;</span>checkpoint)
}
<span class="doccomment">/// Advanced API.
///
/// In most cases use [`get_document_bytes`](Self::get_document_bytes).
</span><span class="kw">fn </span>get_document_bytes_from_block(
block: OwnedBytes,
doc_id: DocId,
checkpoint: <span class="kw-2">&amp;</span>Checkpoint,
) -&gt; <span class="kw">crate</span>::Result&lt;OwnedBytes&gt; {
<span class="kw">let </span>doc_pos = doc_id - checkpoint.doc_range.start;
<span class="kw">let </span>range = block_read_index(<span class="kw-2">&amp;</span>block, doc_pos)<span class="question-mark">?</span>;
<span class="prelude-val">Ok</span>(block.slice(range))
}
<span class="doccomment">/// Iterator over all Documents in their order as they are stored in the doc store.
/// Use this, if you want to extract all Documents from the doc store.
/// The `alive_bitset` has to be forwarded from the `SegmentReader` or the results may be wrong.
</span><span class="kw">pub fn </span>iter&lt;<span class="lifetime">&#39;a</span>: <span class="lifetime">&#39;b</span>, <span class="lifetime">&#39;b</span>&gt;(
<span class="kw-2">&amp;</span><span class="lifetime">&#39;b </span><span class="self">self</span>,
alive_bitset: <span class="prelude-ty">Option</span>&lt;<span class="kw-2">&amp;</span><span class="lifetime">&#39;a </span>AliveBitSet&gt;,
) -&gt; <span class="kw">impl </span>Iterator&lt;Item = <span class="kw">crate</span>::Result&lt;Document&gt;&gt; + <span class="lifetime">&#39;b </span>{
<span class="self">self</span>.iter_raw(alive_bitset).map(|doc_bytes_res| {
<span class="kw">let </span><span class="kw-2">mut </span>doc_bytes = doc_bytes_res<span class="question-mark">?</span>;
<span class="prelude-val">Ok</span>(Document::deserialize(<span class="kw-2">&amp;mut </span>doc_bytes)<span class="question-mark">?</span>)
})
}
<span class="doccomment">/// Iterator over all raw Documents in their order as they are stored in the doc store.
/// Use this, if you want to extract all Documents from the doc store.
/// The `alive_bitset` has to be forwarded from the `SegmentReader` or the results may be wrong.
</span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>iter_raw&lt;<span class="lifetime">&#39;a</span>: <span class="lifetime">&#39;b</span>, <span class="lifetime">&#39;b</span>&gt;(
<span class="kw-2">&amp;</span><span class="lifetime">&#39;b </span><span class="self">self</span>,
alive_bitset: <span class="prelude-ty">Option</span>&lt;<span class="kw-2">&amp;</span><span class="lifetime">&#39;a </span>AliveBitSet&gt;,
) -&gt; <span class="kw">impl </span>Iterator&lt;Item = <span class="kw">crate</span>::Result&lt;OwnedBytes&gt;&gt; + <span class="lifetime">&#39;b </span>{
<span class="kw">let </span>last_doc_id = <span class="self">self
</span>.block_checkpoints()
.last()
.map(|checkpoint| checkpoint.doc_range.end)
.unwrap_or(<span class="number">0</span>);
<span class="kw">let </span><span class="kw-2">mut </span>checkpoint_block_iter = <span class="self">self</span>.block_checkpoints();
<span class="kw">let </span><span class="kw-2">mut </span>curr_checkpoint = checkpoint_block_iter.next();
<span class="kw">let </span><span class="kw-2">mut </span>curr_block = curr_checkpoint
.as_ref()
.map(|checkpoint| <span class="self">self</span>.read_block(checkpoint).map_err(|e| e.kind())); <span class="comment">// map error in order to enable cloning
</span><span class="kw">let </span><span class="kw-2">mut </span>doc_pos = <span class="number">0</span>;
(<span class="number">0</span>..last_doc_id)
.filter_map(<span class="kw">move </span>|doc_id| {
<span class="comment">// filter_map is only used to resolve lifetime issues between the two closures on
// the outer variables
// check move to next checkpoint
</span><span class="kw">if </span>doc_id &gt;= curr_checkpoint.as_ref().unwrap().doc_range.end {
curr_checkpoint = checkpoint_block_iter.next();
curr_block = curr_checkpoint
.as_ref()
.map(|checkpoint| <span class="self">self</span>.read_block(checkpoint).map_err(|e| e.kind()));
doc_pos = <span class="number">0</span>;
}
<span class="kw">let </span>alive = alive_bitset.map_or(<span class="bool-val">true</span>, |bitset| bitset.is_alive(doc_id));
<span class="kw">let </span>res = <span class="kw">if </span>alive {
<span class="prelude-val">Some</span>((curr_block.clone(), doc_pos))
} <span class="kw">else </span>{
<span class="prelude-val">None
</span>};
doc_pos += <span class="number">1</span>;
res
})
.map(<span class="kw">move </span>|(block, doc_pos)| {
<span class="kw">let </span>block = block
.ok_or_else(|| {
DataCorruption::comment_only(
<span class="string">&quot;the current checkpoint in the doc store iterator is none, this \
should never happen&quot;</span>,
)
})<span class="question-mark">?
</span>.map_err(|error_kind| {
std::io::Error::new(error_kind, <span class="string">&quot;error when reading block in doc store&quot;</span>)
})<span class="question-mark">?</span>;
<span class="kw">let </span>range = block_read_index(<span class="kw-2">&amp;</span>block, doc_pos)<span class="question-mark">?</span>;
<span class="prelude-val">Ok</span>(block.slice(range))
})
}
<span class="doccomment">/// Summarize total space usage of this store reader.
</span><span class="kw">pub fn </span>space_usage(<span class="kw-2">&amp;</span><span class="self">self</span>) -&gt; StoreSpaceUsage {
<span class="self">self</span>.space_usage.clone()
}
}
<span class="kw">fn </span>block_read_index(block: <span class="kw-2">&amp;</span>[u8], doc_pos: u32) -&gt; <span class="kw">crate</span>::Result&lt;Range&lt;usize&gt;&gt; {
<span class="kw">let </span>doc_pos = doc_pos <span class="kw">as </span>usize;
<span class="kw">let </span>size_of_u32 = std::mem::size_of::&lt;u32&gt;();
<span class="kw">let </span>index_len_pos = block.len() - size_of_u32;
<span class="kw">let </span>index_len = u32::deserialize(<span class="kw-2">&amp;mut &amp;</span>block[index_len_pos..])<span class="question-mark">? </span><span class="kw">as </span>usize;
<span class="kw">if </span>doc_pos &gt; index_len {
<span class="kw">return </span><span class="prelude-val">Err</span>(<span class="kw">crate</span>::TantivyError::InternalError(
<span class="string">&quot;Attempted to read doc from wrong block&quot;</span>.to_owned(),
));
}
<span class="kw">let </span>index_start = block.len() - (index_len + <span class="number">1</span>) * size_of_u32;
<span class="kw">let </span>index = <span class="kw-2">&amp;</span>block[index_start..index_start + index_len * size_of_u32];
<span class="kw">let </span>start_offset = u32::deserialize(<span class="kw-2">&amp;mut &amp;</span>index[doc_pos * size_of_u32..])<span class="question-mark">? </span><span class="kw">as </span>usize;
<span class="kw">let </span>end_offset = u32::deserialize(<span class="kw-2">&amp;mut &amp;</span>index[(doc_pos + <span class="number">1</span>) * size_of_u32..])
.unwrap_or(index_start <span class="kw">as </span>u32) <span class="kw">as </span>usize;
<span class="prelude-val">Ok</span>(start_offset..end_offset)
}
<span class="attribute">#[cfg(feature = <span class="string">&quot;quickwit&quot;</span>)]
</span><span class="kw">impl </span>StoreReader {
<span class="doccomment">/// Advanced API.
///
/// In most cases use [`get_async`](Self::get_async)
///
/// Loads and decompresses a block asynchronously.
</span><span class="kw">async fn </span>read_block_async(<span class="kw-2">&amp;</span><span class="self">self</span>, checkpoint: <span class="kw-2">&amp;</span>Checkpoint) -&gt; <span class="kw">crate</span>::AsyncIoResult&lt;Block&gt; {
<span class="kw">let </span>cache_key = checkpoint.byte_range.start;
<span class="kw">if let </span><span class="prelude-val">Some</span>(block) = <span class="self">self</span>.cache.get_from_cache(checkpoint.byte_range.start) {
<span class="kw">return </span><span class="prelude-val">Ok</span>(block);
}
<span class="kw">let </span>compressed_block = <span class="self">self
</span>.data
.slice(checkpoint.byte_range.clone())
.read_bytes_async()
.<span class="kw">await</span><span class="question-mark">?</span>;
<span class="kw">let </span>decompressed_block =
OwnedBytes::new(<span class="self">self</span>.decompressor.decompress(compressed_block.as_ref())<span class="question-mark">?</span>);
<span class="self">self</span>.cache
.put_into_cache(cache_key, decompressed_block.clone());
<span class="prelude-val">Ok</span>(decompressed_block)
}
<span class="doccomment">/// Reads raw bytes of a given document asynchronously.
</span><span class="kw">pub async fn </span>get_document_bytes_async(<span class="kw-2">&amp;</span><span class="self">self</span>, doc_id: DocId) -&gt; <span class="kw">crate</span>::Result&lt;OwnedBytes&gt; {
<span class="kw">let </span>checkpoint = <span class="self">self</span>.block_checkpoint(doc_id)<span class="question-mark">?</span>;
<span class="kw">let </span>block = <span class="self">self</span>.read_block_async(<span class="kw-2">&amp;</span>checkpoint).<span class="kw">await</span><span class="question-mark">?</span>;
<span class="self">Self</span>::get_document_bytes_from_block(block, doc_id, <span class="kw-2">&amp;</span>checkpoint)
}
<span class="doccomment">/// Fetches a document asynchronously. Async version of [`get`](Self::get).
</span><span class="kw">pub async fn </span>get_async(<span class="kw-2">&amp;</span><span class="self">self</span>, doc_id: DocId) -&gt; <span class="kw">crate</span>::Result&lt;Document&gt; {
<span class="kw">let </span><span class="kw-2">mut </span>doc_bytes = <span class="self">self</span>.get_document_bytes_async(doc_id).<span class="kw">await</span><span class="question-mark">?</span>;
<span class="prelude-val">Ok</span>(Document::deserialize(<span class="kw-2">&amp;mut </span>doc_bytes)<span class="question-mark">?</span>)
}
}
<span class="attribute">#[cfg(test)]
</span><span class="kw">mod </span>tests {
<span class="kw">use </span>std::path::Path;
<span class="kw">use super</span>::<span class="kw-2">*</span>;
<span class="kw">use </span><span class="kw">crate</span>::directory::RamDirectory;
<span class="kw">use </span><span class="kw">crate</span>::schema::{Document, Field};
<span class="kw">use </span><span class="kw">crate</span>::store::tests::write_lorem_ipsum_store;
<span class="kw">use </span><span class="kw">crate</span>::store::Compressor;
<span class="kw">use </span><span class="kw">crate</span>::Directory;
<span class="kw">const </span>BLOCK_SIZE: usize = <span class="number">16_384</span>;
<span class="kw">fn </span>get_text_field&lt;<span class="lifetime">&#39;a</span>&gt;(doc: <span class="kw-2">&amp;</span><span class="lifetime">&#39;a </span>Document, field: <span class="kw-2">&amp;</span><span class="lifetime">&#39;a </span>Field) -&gt; <span class="prelude-ty">Option</span>&lt;<span class="kw-2">&amp;</span><span class="lifetime">&#39;a </span>str&gt; {
doc.get_first(<span class="kw-2">*</span>field).and_then(|f| f.as_text())
}
<span class="attribute">#[test]
</span><span class="kw">fn </span>test_store_lru_cache() -&gt; <span class="kw">crate</span>::Result&lt;()&gt; {
<span class="kw">let </span>directory = RamDirectory::create();
<span class="kw">let </span>path = Path::new(<span class="string">&quot;store&quot;</span>);
<span class="kw">let </span>writer = directory.open_write(path)<span class="question-mark">?</span>;
<span class="kw">let </span>schema = write_lorem_ipsum_store(writer, <span class="number">500</span>, Compressor::default(), BLOCK_SIZE, <span class="bool-val">true</span>);
<span class="kw">let </span>title = schema.get_field(<span class="string">&quot;title&quot;</span>).unwrap();
<span class="kw">let </span>store_file = directory.open_read(path)<span class="question-mark">?</span>;
<span class="kw">let </span>store = StoreReader::open(store_file, DOCSTORE_CACHE_CAPACITY)<span class="question-mark">?</span>;
<span class="macro">assert_eq!</span>(store.cache.len(), <span class="number">0</span>);
<span class="macro">assert_eq!</span>(store.cache_stats().cache_hits, <span class="number">0</span>);
<span class="macro">assert_eq!</span>(store.cache_stats().cache_misses, <span class="number">0</span>);
<span class="kw">let </span>doc = store.get(<span class="number">0</span>)<span class="question-mark">?</span>;
<span class="macro">assert_eq!</span>(get_text_field(<span class="kw-2">&amp;</span>doc, <span class="kw-2">&amp;</span>title), <span class="prelude-val">Some</span>(<span class="string">&quot;Doc 0&quot;</span>));
<span class="macro">assert_eq!</span>(store.cache.len(), <span class="number">1</span>);
<span class="macro">assert_eq!</span>(store.cache_stats().cache_hits, <span class="number">0</span>);
<span class="macro">assert_eq!</span>(store.cache_stats().cache_misses, <span class="number">1</span>);
<span class="macro">assert_eq!</span>(store.cache.peek_lru(), <span class="prelude-val">Some</span>(<span class="number">0</span>));
<span class="kw">let </span>doc = store.get(<span class="number">499</span>)<span class="question-mark">?</span>;
<span class="macro">assert_eq!</span>(get_text_field(<span class="kw-2">&amp;</span>doc, <span class="kw-2">&amp;</span>title), <span class="prelude-val">Some</span>(<span class="string">&quot;Doc 499&quot;</span>));
<span class="macro">assert_eq!</span>(store.cache.len(), <span class="number">2</span>);
<span class="macro">assert_eq!</span>(store.cache_stats().cache_hits, <span class="number">0</span>);
<span class="macro">assert_eq!</span>(store.cache_stats().cache_misses, <span class="number">2</span>);
<span class="macro">assert_eq!</span>(store.cache.peek_lru(), <span class="prelude-val">Some</span>(<span class="number">0</span>));
<span class="kw">let </span>doc = store.get(<span class="number">0</span>)<span class="question-mark">?</span>;
<span class="macro">assert_eq!</span>(get_text_field(<span class="kw-2">&amp;</span>doc, <span class="kw-2">&amp;</span>title), <span class="prelude-val">Some</span>(<span class="string">&quot;Doc 0&quot;</span>));
<span class="macro">assert_eq!</span>(store.cache.len(), <span class="number">2</span>);
<span class="macro">assert_eq!</span>(store.cache_stats().cache_hits, <span class="number">1</span>);
<span class="macro">assert_eq!</span>(store.cache_stats().cache_misses, <span class="number">2</span>);
<span class="macro">assert_eq!</span>(store.cache.peek_lru(), <span class="prelude-val">Some</span>(<span class="number">11163</span>));
<span class="prelude-val">Ok</span>(())
}
}
</code></pre></div>
</section></div></main><div id="rustdoc-vars" data-root-path="../../../" data-current-crate="tantivy" data-themes="ayu,dark,light" data-resource-suffix="" data-rustdoc-version="1.66.0-nightly (5c8bff74b 2022-10-21)" ></div></body></html>