Upgrade to failure 0.1.2 idioms

Fixes some deprecation warnings in Cargo

Cargo.toml

@@ -23,7 +23,7 @@ crossbeam-utils = "0.5"
 crypto-hash = "0.3.1"
 curl = "0.4.13"
 env_logger = "0.5.4"
-failure = "0.1.1"
+failure = "0.1.2"
 filetime = "0.2"
 flate2 = "1.0"
 fs2 = "0.4"

src/cargo/core/compiler/fingerprint.rs

@@ -685,7 +685,7 @@ fn log_compare(unit: &Unit, compare: &CargoResult<()>) {
     };
     info!("fingerprint error for {}: {}", unit.pkg, ce);
 
-    for cause in ce.causes().skip(1) {
+    for cause in ce.iter_causes() {
         info!("  cause: {}", cause);
     }
 }

src/cargo/lib.rs

@@ -184,13 +184,13 @@ fn handle_cause(cargo_err: &Error, shell: &mut Shell) -> bool {
     if verbose == Verbose {
         // The first error has already been printed to the shell
         // Print all remaining errors
-        for err in cargo_err.causes().skip(1) {
+        for err in cargo_err.iter_causes() {
             print(&err.to_string(), shell);
         }
     } else {
         // The first error has already been printed to the shell
         // Print remaining errors until one marked as Internal appears
-        for err in cargo_err.causes().skip(1) {
+        for err in cargo_err.iter_causes() {
             if err.downcast_ref::<Internal>().is_some() {
                 return false;
             }

src/cargo/util/config.rs

@@ -921,7 +921,7 @@ impl fmt::Display for ConfigError {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         let message = self
             .error
-            .causes()
+            .iter_chain()
             .map(|e| e.to_string())
             .collect::<Vec<_>>()
             .join("\nCaused by:\n  ");

src/cargo/util/errors.rs

@@ -56,7 +56,7 @@ impl Internal {
 
 impl Fail for Internal {
     fn cause(&self) -> Option<&Fail> {
-        self.inner.cause().cause()
+        self.inner.as_fail().cause()
     }
 }
 

src/cargo/util/network.rs

@@ -7,7 +7,7 @@ use util::Config;
 use util::errors::{CargoResult, HttpNot200};
 
 fn maybe_spurious(err: &Error) -> bool {
-    for e in err.causes() {
+    for e in err.iter_chain() {
         if let Some(git_err) = e.downcast_ref::<git2::Error>() {
             match git_err.class() {
                 git2::ErrorClass::Net | git2::ErrorClass::Os => return true,

tests/testsuite/config.rs

@@ -70,7 +70,7 @@ fn new_config(env: &[(&str, &str)]) -> Config {
 
 fn assert_error(error: CargoError, msgs: &str) {
     let causes = error
-        .causes()
+        .iter_chain()
         .map(|e| e.to_string())
         .collect::<Vec<_>>()
         .join("\n");

tests/testsuite/support/mod.rs

@@ -1169,7 +1169,7 @@ impl<'a> ham::Matcher<&'a mut ProcessBuilder> for Execs {
                         return self.match_output(out);
                     }
                 let mut s = format!("could not exec process {}: {}", process, e);
-                for cause in e.causes() {
+                for cause in e.iter_causes() {
                     s.push_str(&format!("\ncaused by: {}", cause));
                 }
                 Err(s)