Use io::Error::downcast in 1.79 (#1754)

* Bump msrv of binstalk-downloader, binstalk and cargo-binstall to 1.79

* Update From<io::Error> for DownloadError

to use io::Error::downcast

* Update From<io::Error> for BinstallError

* fix dmt

crates/bin/Cargo.toml

@@ -4,7 +4,7 @@ description = "Binary installation for rust projects"
 repository = "https://github.com/cargo-bins/cargo-binstall"
 documentation = "https://docs.rs/cargo-binstall"
 version = "1.6.9"
-rust-version = "1.70.0"
+rust-version = "1.79.0"
 authors = ["ryan <ryan@kurte.nz>"]
 edition = "2021"
 license = "GPL-3.0-only"

crates/binstalk-downloader/Cargo.toml

@@ -4,7 +4,7 @@ description = "The binstall toolkit for downloading and extracting file"
 repository = "https://github.com/cargo-bins/cargo-binstall"
 documentation = "https://docs.rs/binstalk-downloader"
 version = "0.11.2"
-rust-version = "1.70.0"
+rust-version = "1.79.0"
 authors = ["ryan <ryan@kurte.nz>"]
 edition = "2021"
 license = "Apache-2.0 OR MIT"

crates/binstalk-downloader/src/download.rs

@@ -44,20 +44,8 @@ pub enum DownloadError {
 
 impl From<io::Error> for DownloadError {
     fn from(err: io::Error) -> Self {
-        if err.get_ref().is_some() {
-            let kind = err.kind();
-
-            let inner = err
-                .into_inner()
-                .expect("err.get_ref() returns Some, so err.into_inner() should also return Some");
-
-            inner
-                .downcast()
-                .map(|b| *b)
-                .unwrap_or_else(|err| DownloadError::Io(io::Error::new(kind, err)))
-        } else {
-            DownloadError::Io(err)
-        }
+        err.downcast::<DownloadError>()
+            .unwrap_or_else(DownloadError::Io)
     }
 }
 

crates/binstalk/Cargo.toml

@@ -4,7 +4,7 @@ description = "The binstall toolkit (library interface)"
 repository = "https://github.com/cargo-bins/cargo-binstall"
 documentation = "https://docs.rs/binstalk"
 version = "0.24.0"
-rust-version = "1.65.0"
+rust-version = "1.79.0"
 authors = ["ryan <ryan@kurte.nz>"]
 edition = "2021"
 license = "GPL-3.0-only"

crates/binstalk/src/errors.rs

@@ -530,20 +530,8 @@ impl Termination for BinstallError {
 
 impl From<io::Error> for BinstallError {
     fn from(err: io::Error) -> Self {
-        if err.get_ref().is_some() {
-            let kind = err.kind();
-
-            let inner = err
-                .into_inner()
-                .expect("err.get_ref() returns Some, so err.into_inner() should also return Some");
-
-            inner
-                .downcast()
-                .map(|b| *b)
-                .unwrap_or_else(|err| BinstallError::Io(io::Error::new(kind, err)))
-        } else {
-            BinstallError::Io(err)
-        }
+        err.downcast::<BinstallError>()
+            .unwrap_or_else(BinstallError::Io)
     }
 }