more comments, sync check

Signed-off-by: Alex Chi <iskyzh@gmail.com>

mini-lsm-starter/src/table/builder.rs

@@ -0,0 +1,30 @@
+#![allow(unused_variables)] // TODO(you): remove this lint after implementing this mod
+#![allow(dead_code)] // TODO(you): remove this lint after implementing this mod
+
+use anyhow::Result;
+use std::path::Path;
+
+use super::{BlockMeta, SsTable};
+
+/// Builds an SSTable from key-value pairs.
+pub struct SsTableBuilder {
+    pub(super) meta: Vec<BlockMeta>,
+}
+
+impl SsTableBuilder {
+    /// Create a builder based on target SST size and target block size.
+    pub fn new(target_size: usize, block_size: usize) -> Self {
+        unimplemented!()
+    }
+
+    /// Adds a key-value pair to SSTable, return false when SST full.
+    #[must_use]
+    pub fn add(&mut self, key: &[u8], value: &[u8]) -> bool {
+        unimplemented!()
+    }
+
+    /// Builds the SSTable and writes it to the given path. No need to actually write to disk until chapter 4 block cache.
+    pub fn build(self, path: impl AsRef<Path>) -> Result<SsTable> {
+        unimplemented!()
+    }
+}

mini-lsm-starter/src/table/iterator.rs

@@ -0,0 +1,53 @@
+#![allow(unused_variables)] // TODO(you): remove this lint after implementing this mod
+#![allow(dead_code)] // TODO(you): remove this lint after implementing this mod
+
+use anyhow::Result;
+use std::sync::Arc;
+
+use super::SsTable;
+
+/// An iterator over the contents of an SSTable.
+pub struct SsTableIterator {}
+
+impl SsTableIterator {
+    /// Create a new iterator and seek to the first key-value pair.
+    pub fn create_and_seek_to_first(table: Arc<SsTable>) -> Result<Self> {
+        unimplemented!()
+    }
+
+    /// Seek to the first key-value pair.
+    pub fn seek_to_first(&mut self) -> Result<()> {
+        unimplemented!()
+    }
+
+    /// Create a new iterator and seek to the first key-value pair which >= `key`.
+    pub fn create_and_seek_to_key(table: Arc<SsTable>, key: &[u8]) -> Result<Self> {
+        unimplemented!()
+    }
+
+    /// Seek to the first key-value pair which >= `key`.
+    pub fn seek_to_key(&mut self, key: &[u8]) -> Result<()> {
+        unimplemented!()
+    }
+
+    /// Get the current key.
+    pub fn key(&self) -> &[u8] {
+        unimplemented!()
+    }
+
+    /// Get the current value.
+    pub fn value(&self) -> &[u8] {
+        unimplemented!()
+    }
+
+    /// Check if the iterator is valid.
+    pub fn is_valid(&self) -> bool {
+        unimplemented!()
+    }
+
+    /// Move to the next key-value pair.
+    #[allow(clippy::should_implement_trait)]
+    pub fn next(&mut self) -> Result<()> {
+        unimplemented!()
+    }
+}

mini-lsm-starter/src/table/tests.rs

@@ -0,0 +1 @@
+