diff rust/hg-core/src/lib.rs @ 42749:7ceded4419a3

rust-dirstate: use EntryState enum instead of literals

This improves code readability quite a bit, while also adding a layer of
safety because we're checking the state byte against the enum.

Differential Revision: https://phab.mercurial-scm.org/D6629

--- a/rust/hg-core/src/lib.rs	Tue Jul 09 11:49:49 2019 +0200
+++ b/rust/hg-core/src/lib.rs	Tue Jul 09 12:15:09 2019 +0200
@@ -11,7 +11,8 @@
 pub use dirstate::{
     dirs_multiset::DirsMultiset,
     parsers::{pack_dirstate, parse_dirstate, PARENT_SIZE},
-    CopyMap, DirsIterable, DirstateEntry, DirstateParents, StateMap,
+    CopyMap, DirsIterable, DirstateEntry, DirstateParents, EntryState,
+    StateMap,
 };
 mod filepatterns;
 pub mod utils;
@@ -62,6 +63,24 @@
     Damaged,
 }
 
+impl From<std::io::Error> for DirstateParseError {
+    fn from(e: std::io::Error) -> Self {
+        DirstateParseError::CorruptedEntry(e.to_string())
+    }
+}
+
+impl ToString for DirstateParseError {
+    fn to_string(&self) -> String {
+        use crate::DirstateParseError::*;
+        match self {
+            TooLittleData => "Too little data for dirstate.".to_string(),
+            Overflow => "Overflow in dirstate.".to_string(),
+            CorruptedEntry(e) => format!("Corrupted entry: {:?}.", e),
+            Damaged => "Dirstate appears to be damaged.".to_string(),
+        }
+    }
+}
+
 #[derive(Debug, PartialEq)]
 pub enum DirstatePackError {
     CorruptedEntry(String),
@@ -69,21 +88,33 @@
     BadSize(usize, usize),
 }
 
+impl From<std::io::Error> for DirstatePackError {
+    fn from(e: std::io::Error) -> Self {
+        DirstatePackError::CorruptedEntry(e.to_string())
+    }
+}
 #[derive(Debug, PartialEq)]
 pub enum DirstateMapError {
     PathNotFound(Vec<u8>),
     EmptyPath,
 }
 
-impl From<std::io::Error> for DirstatePackError {
-    fn from(e: std::io::Error) -> Self {
-        DirstatePackError::CorruptedEntry(e.to_string())
+pub enum DirstateError {
+    Parse(DirstateParseError),
+    Pack(DirstatePackError),
+    Map(DirstateMapError),
+    IO(std::io::Error),
+}
+
+impl From<DirstateParseError> for DirstateError {
+    fn from(e: DirstateParseError) -> Self {
+        DirstateError::Parse(e)
     }
 }
 
-impl From<std::io::Error> for DirstateParseError {
-    fn from(e: std::io::Error) -> Self {
-        DirstateParseError::CorruptedEntry(e.to_string())
+impl From<DirstatePackError> for DirstateError {
+    fn from(e: DirstatePackError) -> Self {
+        DirstateError::Pack(e)
     }
 }
 
@@ -103,3 +134,15 @@
         PatternFileError::IO(e)
     }
 }
+
+impl From<DirstateMapError> for DirstateError {
+    fn from(e: DirstateMapError) -> Self {
+        DirstateError::Map(e)
+    }
+}
+
+impl From<std::io::Error> for DirstateError {
+    fn from(e: std::io::Error) -> Self {
+        DirstateError::IO(e)
+    }
+}