chore(docs): refine part 1, 2

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

mini-lsm-book/src/00-overview.md

@@ -1,5 +1,7 @@
 # Overview
 
+<!-- toc -->
+
 In this tutorial, you will learn how to build a simple LSM-Tree storage engine in the Rust programming language.
 
 ## What is LSM, and Why LSM?

mini-lsm-book/src/01-block.md

@@ -1,5 +1,7 @@
 # Block Builder and Block Iterator
 
+<!-- toc -->
+
 In this part, you will need to modify:
 
 * `src/block/builder.rs`

mini-lsm-starter/src/table.rs

@@ -57,7 +57,11 @@ impl FileObject {
     }
 }
 
-pub struct SsTable {}
+pub struct SsTable {
+    file: FileObject,
+    block_metas: Vec<BlockMeta>,
+    block_meta_offset: usize,
+}
 
 impl SsTable {
     /// Open SSTable from a file.

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

@@ -9,6 +9,7 @@ use super::{BlockMeta, SsTable};
 /// Builds an SSTable from key-value pairs.
 pub struct SsTableBuilder {
     pub(super) meta: Vec<BlockMeta>,
+    // Add other fields you need.
 }
 
 impl SsTableBuilder {

xtask/src/main.rs

@@ -8,6 +8,7 @@ use duct::cmd;
 #[derive(clap::Subcommand, Debug)]
 enum CopyTestAction {
     Day1,
+    Day2,
 }
 
 #[derive(clap::Subcommand, Debug)]
@@ -132,6 +133,14 @@ fn copy_test_case(test: CopyTestAction) -> Result<()> {
             )
             .run()?;
         }
+        CopyTestAction::Day2 => {
+            cmd!(
+                "cp",
+                "mini-lsm/src/table/tests.rs",
+                "mini-lsm-starter/src/table/tests.rs"
+            )
+            .run()?;
+        }
     }
     Ok(())
 }