rust: add logging utils

This change adds the `log` crate, the community-approved logging facade backed
by Rust core developers as well as the logging-consumer crate `simple_logger`
to build a foundation for logging from Rust.

Using this setup allows us to choose how to log depending on the way `hg-core`
is used: if it's within the context of `hg-cpython`, we might not want to use
it the same way as with a direct cli for example.

Differential Revision: https://phab.mercurial-scm.org/D8252

rust/Cargo.lock

@@ -2,10 +2,10 b''
 # It is not intended for manual editing.
 [[package]]
 name = "aho-corasick"
-version = "0.7.8"
+version = "0.7.10"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "memchr 2.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "memchr 2.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -21,8 +21,8 b' name = "atty"'
 version = "0.2.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "hermit-abi 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.66 (registry+https://github.com/rust-lang/crates.io-index)",
+ "hermit-abi 0.1.8 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.67 (registry+https://github.com/rust-lang/crates.io-index)",
  "winapi 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -43,18 +43,10 b' source = "registry+https://github.com/ru'
 
 [[package]]
 name = "byteorder"
-version = "1.3.2"
+version = "1.3.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
-name = "c2-chacha"
-version = "0.2.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "ppv-lite86 0.2.6 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
-[[package]]
 name = "cc"
 version = "1.0.50"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -65,6 +57,16 b' version = "0.1.10"'
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
+name = "chrono"
+version = "0.4.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "num-integer 0.1.42 (registry+https://github.com/rust-lang/crates.io-index)",
+ "num-traits 0.2.11 (registry+https://github.com/rust-lang/crates.io-index)",
+ "time 0.1.42 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
 name = "clap"
 version = "2.33.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -87,11 +89,21 b' dependencies = ['
 ]
 
 [[package]]
+name = "colored"
+version = "1.9.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "atty 0.2.14 (registry+https://github.com/rust-lang/crates.io-index)",
+ "lazy_static 1.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "winapi 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
 name = "cpython"
 version = "0.4.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "libc 0.2.66 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.67 (registry+https://github.com/rust-lang/crates.io-index)",
  "num-traits 0.2.11 (registry+https://github.com/rust-lang/crates.io-index)",
  "python27-sys 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "python3-sys 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -104,10 +116,10 b' source = "registry+https://github.com/ru'
 dependencies = [
  "cfg-if 0.1.10 (registry+https://github.com/rust-lang/crates.io-index)",
  "crossbeam-channel 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "crossbeam-deque 0.7.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "crossbeam-epoch 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "crossbeam-deque 0.7.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "crossbeam-epoch 0.8.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "crossbeam-queue 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "crossbeam-utils 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "crossbeam-utils 0.7.2 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -115,30 +127,32 b' name = "crossbeam-channel"'
 version = "0.4.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "crossbeam-utils 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "crossbeam-utils 0.7.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "maybe-uninit 2.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "crossbeam-deque"
-version = "0.7.2"
+version = "0.7.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "crossbeam-epoch 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "crossbeam-utils 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "crossbeam-epoch 0.8.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "crossbeam-utils 0.7.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "maybe-uninit 2.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "crossbeam-epoch"
-version = "0.8.0"
+version = "0.8.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "autocfg 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)",
+ "autocfg 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "cfg-if 0.1.10 (registry+https://github.com/rust-lang/crates.io-index)",
- "crossbeam-utils 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "crossbeam-utils 0.7.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "lazy_static 1.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "maybe-uninit 2.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "memoffset 0.5.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "scopeguard 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "scopeguard 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -147,26 +161,26 b' version = "0.2.1"'
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "cfg-if 0.1.10 (registry+https://github.com/rust-lang/crates.io-index)",
- "crossbeam-utils 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "crossbeam-utils 0.7.2 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "crossbeam-utils"
-version = "0.7.0"
+version = "0.7.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "autocfg 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)",
+ "autocfg 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "cfg-if 0.1.10 (registry+https://github.com/rust-lang/crates.io-index)",
  "lazy_static 1.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "ctor"
-version = "0.1.12"
+version = "0.1.13"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "quote 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "syn 1.0.14 (registry+https://github.com/rust-lang/crates.io-index)",
+ "quote 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "syn 1.0.16 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -190,35 +204,36 b' version = "0.1.14"'
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "cfg-if 0.1.10 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.66 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.67 (registry+https://github.com/rust-lang/crates.io-index)",
  "wasi 0.9.0+wasi-snapshot-preview1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "hermit-abi"
-version = "0.1.6"
+version = "0.1.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "libc 0.2.66 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.67 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "hex"
-version = "0.4.0"
+version = "0.4.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "hg-core"
 version = "0.1.0"
 dependencies = [
- "byteorder 1.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "byteorder 1.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "cc 1.0.50 (registry+https://github.com/rust-lang/crates.io-index)",
  "clap 2.33.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "crossbeam 0.7.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "hex 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "hex 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "lazy_static 1.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.66 (registry+https://github.com/rust-lang/crates.io-index)",
- "memchr 2.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.67 (registry+https://github.com/rust-lang/crates.io-index)",
+ "log 0.4.8 (registry+https://github.com/rust-lang/crates.io-index)",
+ "memchr 2.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "memmap 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "pretty_assertions 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "rand 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -236,7 +251,8 b' version = "0.1.0"'
 dependencies = [
  "cpython 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "hg-core 0.1.0",
- "libc 0.2.66 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.67 (registry+https://github.com/rust-lang/crates.io-index)",
+ "simple_logger 1.6.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -246,17 +262,25 b' source = "registry+https://github.com/ru'
 
 [[package]]
 name = "libc"
-version = "0.2.66"
+version = "0.2.67"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
+name = "log"
+version = "0.4.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "cfg-if 0.1.10 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
 name = "maybe-uninit"
 version = "2.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "memchr"
-version = "2.3.0"
+version = "2.3.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
@@ -264,7 +288,7 b' name = "memmap"'
 version = "0.7.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "libc 0.2.66 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.67 (registry+https://github.com/rust-lang/crates.io-index)",
  "winapi 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -277,6 +301,15 b' dependencies = ['
 ]
 
 [[package]]
+name = "num-integer"
+version = "0.1.42"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "autocfg 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "num-traits 0.2.11 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
 name = "num-traits"
 version = "0.2.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -289,8 +322,8 b' name = "num_cpus"'
 version = "1.12.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "hermit-abi 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.66 (registry+https://github.com/rust-lang/crates.io-index)",
+ "hermit-abi 0.1.8 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.67 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -312,14 +345,14 b' version = "0.6.1"'
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "ansi_term 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "ctor 0.1.12 (registry+https://github.com/rust-lang/crates.io-index)",
+ "ctor 0.1.13 (registry+https://github.com/rust-lang/crates.io-index)",
  "difference 2.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "output_vt100 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "proc-macro2"
-version = "1.0.8"
+version = "1.0.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "unicode-xid 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -330,7 +363,7 b' name = "python27-sys"'
 version = "0.4.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "libc 0.2.66 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.67 (registry+https://github.com/rust-lang/crates.io-index)",
  "regex 1.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -339,16 +372,16 b' name = "python3-sys"'
 version = "0.4.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "libc 0.2.66 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.67 (registry+https://github.com/rust-lang/crates.io-index)",
  "regex 1.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "quote"
-version = "1.0.2"
+version = "1.0.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "proc-macro2 1.0.8 (registry+https://github.com/rust-lang/crates.io-index)",
+ "proc-macro2 1.0.9 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -357,7 +390,7 b' version = "0.6.5"'
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "autocfg 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.66 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.67 (registry+https://github.com/rust-lang/crates.io-index)",
  "rand_chacha 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "rand_core 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "rand_hc 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -375,8 +408,8 b' version = "0.7.3"'
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "getrandom 0.1.14 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.66 (registry+https://github.com/rust-lang/crates.io-index)",
- "rand_chacha 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.67 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_chacha 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "rand_core 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "rand_hc 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -392,10 +425,10 b' dependencies = ['
 
 [[package]]
 name = "rand_chacha"
-version = "0.2.1"
+version = "0.2.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "c2-chacha 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "ppv-lite86 0.2.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "rand_core 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -449,7 +482,7 b' name = "rand_jitter"'
 version = "0.1.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "libc 0.2.66 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.67 (registry+https://github.com/rust-lang/crates.io-index)",
  "rand_core 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "winapi 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -461,7 +494,7 b' source = "registry+https://github.com/ru'
 dependencies = [
  "cloudabi 0.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "fuchsia-cprng 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.66 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.67 (registry+https://github.com/rust-lang/crates.io-index)",
  "rand_core 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "rdrand 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "winapi 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -489,7 +522,7 b' name = "rayon"'
 version = "1.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "crossbeam-deque 0.7.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "crossbeam-deque 0.7.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "either 1.5.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "rayon-core 1.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -499,9 +532,9 b' name = "rayon-core"'
 version = "1.7.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "crossbeam-deque 0.7.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "crossbeam-deque 0.7.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "crossbeam-queue 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "crossbeam-utils 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "crossbeam-utils 0.7.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "lazy_static 1.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "num_cpus 1.12.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -524,15 +557,15 b' name = "regex"'
 version = "1.3.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "aho-corasick 0.7.8 (registry+https://github.com/rust-lang/crates.io-index)",
- "memchr 2.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "regex-syntax 0.6.14 (registry+https://github.com/rust-lang/crates.io-index)",
+ "aho-corasick 0.7.10 (registry+https://github.com/rust-lang/crates.io-index)",
+ "memchr 2.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "regex-syntax 0.6.16 (registry+https://github.com/rust-lang/crates.io-index)",
  "thread_local 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "regex-syntax"
-version = "0.6.14"
+version = "0.6.16"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
@@ -561,7 +594,7 b' dependencies = ['
 
 [[package]]
 name = "scopeguard"
-version = "1.0.0"
+version = "1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
@@ -578,17 +611,29 b' version = "0.7.0"'
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
+name = "simple_logger"
+version = "1.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "atty 0.2.14 (registry+https://github.com/rust-lang/crates.io-index)",
+ "chrono 0.4.11 (registry+https://github.com/rust-lang/crates.io-index)",
+ "colored 1.9.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "log 0.4.8 (registry+https://github.com/rust-lang/crates.io-index)",
+ "winapi 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
 name = "strsim"
 version = "0.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "syn"
-version = "1.0.14"
+version = "1.0.16"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "proc-macro2 1.0.8 (registry+https://github.com/rust-lang/crates.io-index)",
- "quote 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "proc-macro2 1.0.9 (registry+https://github.com/rust-lang/crates.io-index)",
+ "quote 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "unicode-xid 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -598,7 +643,7 b' version = "3.1.0"'
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "cfg-if 0.1.10 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.66 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.67 (registry+https://github.com/rust-lang/crates.io-index)",
  "rand 0.7.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "redox_syscall 0.1.56 (registry+https://github.com/rust-lang/crates.io-index)",
  "remove_dir_all 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -622,6 +667,16 b' dependencies = ['
 ]
 
 [[package]]
+name = "time"
+version = "0.1.42"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "libc 0.2.67 (registry+https://github.com/rust-lang/crates.io-index)",
+ "redox_syscall 0.1.56 (registry+https://github.com/rust-lang/crates.io-index)",
+ "winapi 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
 name = "twox-hash"
 version = "1.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -677,51 +732,54 b' version = "0.4.0"'
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [metadata]
-"checksum aho-corasick 0.7.8 (registry+https://github.com/rust-lang/crates.io-index)" = "743ad5a418686aad3b87fd14c43badd828cf26e214a00f92a384291cf22e1811"
+"checksum aho-corasick 0.7.10 (registry+https://github.com/rust-lang/crates.io-index)" = "8716408b8bc624ed7f65d223ddb9ac2d044c0547b6fa4b0d554f3a9540496ada"
 "checksum ansi_term 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)" = "ee49baf6cb617b853aa8d93bf420db2383fab46d314482ca2803b40d5fde979b"
 "checksum atty 0.2.14 (registry+https://github.com/rust-lang/crates.io-index)" = "d9b39be18770d11421cdb1b9947a45dd3f37e93092cbf377614828a319d5fee8"
 "checksum autocfg 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)" = "1d49d90015b3c36167a20fe2810c5cd875ad504b39cff3d4eae7977e6b7c1cb2"
 "checksum autocfg 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "f8aac770f1885fd7e387acedd76065302551364496e46b3dd00860b2f8359b9d"
 "checksum bitflags 1.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "cf1de2fe8c75bc145a2f577add951f8134889b4795d47466a54a5c846d691693"
-"checksum byteorder 1.3.2 (registry+https://github.com/rust-lang/crates.io-index)" = "a7c3dd8985a7111efc5c80b44e23ecdd8c007de8ade3b96595387e812b957cf5"
-"checksum c2-chacha 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)" = "214238caa1bf3a496ec3392968969cab8549f96ff30652c9e56885329315f6bb"
+"checksum byteorder 1.3.4 (registry+https://github.com/rust-lang/crates.io-index)" = "08c48aae112d48ed9f069b33538ea9e3e90aa263cfa3d1c24309612b1f7472de"
 "checksum cc 1.0.50 (registry+https://github.com/rust-lang/crates.io-index)" = "95e28fa049fda1c330bcf9d723be7663a899c4679724b34c81e9f5a326aab8cd"
 "checksum cfg-if 0.1.10 (registry+https://github.com/rust-lang/crates.io-index)" = "4785bdd1c96b2a846b2bd7cc02e86b6b3dbf14e7e53446c4f54c92a361040822"
+"checksum chrono 0.4.11 (registry+https://github.com/rust-lang/crates.io-index)" = "80094f509cf8b5ae86a4966a39b3ff66cd7e2a3e594accec3743ff3fabeab5b2"
 "checksum clap 2.33.0 (registry+https://github.com/rust-lang/crates.io-index)" = "5067f5bb2d80ef5d68b4c87db81601f0b75bca627bc2ef76b141d7b846a3c6d9"
 "checksum cloudabi 0.0.3 (registry+https://github.com/rust-lang/crates.io-index)" = "ddfc5b9aa5d4507acaf872de71051dfd0e309860e88966e1051e462a077aac4f"
+"checksum colored 1.9.3 (registry+https://github.com/rust-lang/crates.io-index)" = "f4ffc801dacf156c5854b9df4f425a626539c3a6ef7893cc0c5084a23f0b6c59"
 "checksum cpython 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)" = "bfaf3847ab963e40c4f6dd8d6be279bdf74007ae2413786a0dcbb28c52139a95"
 "checksum crossbeam 0.7.3 (registry+https://github.com/rust-lang/crates.io-index)" = "69323bff1fb41c635347b8ead484a5ca6c3f11914d784170b158d8449ab07f8e"
 "checksum crossbeam-channel 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)" = "cced8691919c02aac3cb0a1bc2e9b73d89e832bf9a06fc579d4e71b68a2da061"
-"checksum crossbeam-deque 0.7.2 (registry+https://github.com/rust-lang/crates.io-index)" = "c3aa945d63861bfe624b55d153a39684da1e8c0bc8fba932f7ee3a3c16cea3ca"
-"checksum crossbeam-epoch 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)" = "5064ebdbf05ce3cb95e45c8b086f72263f4166b29b97f6baff7ef7fe047b55ac"
+"checksum crossbeam-deque 0.7.3 (registry+https://github.com/rust-lang/crates.io-index)" = "9f02af974daeee82218205558e51ec8768b48cf524bd01d550abe5573a608285"
+"checksum crossbeam-epoch 0.8.2 (registry+https://github.com/rust-lang/crates.io-index)" = "058ed274caafc1f60c4997b5fc07bf7dc7cca454af7c6e81edffe5f33f70dace"
 "checksum crossbeam-queue 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "c695eeca1e7173472a32221542ae469b3e9aac3a4fc81f7696bcad82029493db"
-"checksum crossbeam-utils 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)" = "ce446db02cdc3165b94ae73111e570793400d0794e46125cc4056c81cbb039f4"
-"checksum ctor 0.1.12 (registry+https://github.com/rust-lang/crates.io-index)" = "cd8ce37ad4184ab2ce004c33bf6379185d3b1c95801cab51026bd271bf68eedc"
+"checksum crossbeam-utils 0.7.2 (registry+https://github.com/rust-lang/crates.io-index)" = "c3c7c73a2d1e9fc0886a08b93e98eb643461230d5f1925e4036204d5f2e261a8"
+"checksum ctor 0.1.13 (registry+https://github.com/rust-lang/crates.io-index)" = "47c5e5ac752e18207b12e16b10631ae5f7f68f8805f335f9b817ead83d9ffce1"
 "checksum difference 2.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "524cbf6897b527295dff137cec09ecf3a05f4fddffd7dfcd1585403449e74198"
 "checksum either 1.5.3 (registry+https://github.com/rust-lang/crates.io-index)" = "bb1f6b1ce1c140482ea30ddd3335fc0024ac7ee112895426e0a629a6c20adfe3"
 "checksum fuchsia-cprng 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "a06f77d526c1a601b7c4cdd98f54b5eaabffc14d5f2f0296febdc7f357c6d3ba"
 "checksum getrandom 0.1.14 (registry+https://github.com/rust-lang/crates.io-index)" = "7abc8dd8451921606d809ba32e95b6111925cd2906060d2dcc29c070220503eb"
-"checksum hermit-abi 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)" = "eff2656d88f158ce120947499e971d743c05dbcbed62e5bd2f38f1698bbc3772"
-"checksum hex 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "023b39be39e3a2da62a94feb433e91e8bcd37676fbc8bea371daf52b7a769a3e"
+"checksum hermit-abi 0.1.8 (registry+https://github.com/rust-lang/crates.io-index)" = "1010591b26bbfe835e9faeabeb11866061cc7dcebffd56ad7d0942d0e61aefd8"
+"checksum hex 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)" = "644f9158b2f133fd50f5fb3242878846d9eb792e445c893805ff0e3824006e35"
 "checksum lazy_static 1.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "e2abad23fbc42b3700f2f279844dc832adb2b2eb069b2df918f455c4e18cc646"
-"checksum libc 0.2.66 (registry+https://github.com/rust-lang/crates.io-index)" = "d515b1f41455adea1313a4a2ac8a8a477634fbae63cc6100e3aebb207ce61558"
+"checksum libc 0.2.67 (registry+https://github.com/rust-lang/crates.io-index)" = "eb147597cdf94ed43ab7a9038716637d2d1bf2bc571da995d0028dec06bd3018"
+"checksum log 0.4.8 (registry+https://github.com/rust-lang/crates.io-index)" = "14b6052be84e6b71ab17edffc2eeabf5c2c3ae1fdb464aae35ac50c67a44e1f7"
 "checksum maybe-uninit 2.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "60302e4db3a61da70c0cb7991976248362f30319e88850c487b9b95bbf059e00"
-"checksum memchr 2.3.0 (registry+https://github.com/rust-lang/crates.io-index)" = "3197e20c7edb283f87c071ddfc7a2cca8f8e0b888c242959846a6fce03c72223"
+"checksum memchr 2.3.3 (registry+https://github.com/rust-lang/crates.io-index)" = "3728d817d99e5ac407411fa471ff9800a778d88a24685968b36824eaf4bee400"
 "checksum memmap 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)" = "6585fd95e7bb50d6cc31e20d4cf9afb4e2ba16c5846fc76793f11218da9c475b"
 "checksum memoffset 0.5.3 (registry+https://github.com/rust-lang/crates.io-index)" = "75189eb85871ea5c2e2c15abbdd541185f63b408415e5051f5cac122d8c774b9"
+"checksum num-integer 0.1.42 (registry+https://github.com/rust-lang/crates.io-index)" = "3f6ea62e9d81a77cd3ee9a2a5b9b609447857f3d358704331e4ef39eb247fcba"
 "checksum num-traits 0.2.11 (registry+https://github.com/rust-lang/crates.io-index)" = "c62be47e61d1842b9170f0fdeec8eba98e60e90e5446449a0545e5152acd7096"
 "checksum num_cpus 1.12.0 (registry+https://github.com/rust-lang/crates.io-index)" = "46203554f085ff89c235cd12f7075f3233af9b11ed7c9e16dfe2560d03313ce6"
 "checksum output_vt100 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)" = "53cdc5b785b7a58c5aad8216b3dfa114df64b0b06ae6e1501cef91df2fbdf8f9"
 "checksum ppv-lite86 0.2.6 (registry+https://github.com/rust-lang/crates.io-index)" = "74490b50b9fbe561ac330df47c08f3f33073d2d00c150f719147d7c54522fa1b"
 "checksum pretty_assertions 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)" = "3f81e1644e1b54f5a68959a29aa86cde704219254669da328ecfdf6a1f09d427"
-"checksum proc-macro2 1.0.8 (registry+https://github.com/rust-lang/crates.io-index)" = "3acb317c6ff86a4e579dfa00fc5e6cca91ecbb4e7eb2df0468805b674eb88548"
+"checksum proc-macro2 1.0.9 (registry+https://github.com/rust-lang/crates.io-index)" = "6c09721c6781493a2a492a96b5a5bf19b65917fe6728884e7c44dd0c60ca3435"
 "checksum python27-sys 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)" = "67cb041de8615111bf224dd75667af5f25c6e032118251426fed7f1b70ce4c8c"
 "checksum python3-sys 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)" = "90af11779515a1e530af60782d273b59ac79d33b0e253c071a728563957c76d4"
-"checksum quote 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)" = "053a8c8bcc71fcce321828dc897a98ab9760bef03a4fc36693c231e5b3216cfe"
+"checksum quote 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)" = "2bdc6c187c65bca4260c9011c9e3132efe4909da44726bad24cf7572ae338d7f"
 "checksum rand 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)" = "6d71dacdc3c88c1fde3885a3be3fbab9f35724e6ce99467f7d9c5026132184ca"
 "checksum rand 0.7.3 (registry+https://github.com/rust-lang/crates.io-index)" = "6a6b1679d49b24bbfe0c803429aa1874472f50d9b363131f0e89fc356b544d03"
 "checksum rand_chacha 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "556d3a1ca6600bfcbab7c7c91ccb085ac7fbbcd70e008a98742e7847f4f7bcef"
-"checksum rand_chacha 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "03a2a90da8c7523f554344f921aa97283eadf6ac484a6d2a7d0212fa7f8d6853"
+"checksum rand_chacha 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "f4c8ed856279c9737206bf725bf36935d8666ead7aa69b52be55af369d193402"
 "checksum rand_core 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)" = "7a6fdeb83b075e8266dcc8762c22776f6877a63111121f5f8c7411e5be7eed4b"
 "checksum rand_core 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)" = "9c33a3c44ca05fa6f1807d8e6743f3824e8509beca625669633be0acbdf509dc"
 "checksum rand_core 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)" = "90bde5296fc891b0cef12a6d03ddccc162ce7b2aff54160af9338f8d40df6d19"
@@ -737,18 +795,20 b' source = "registry+https://github.com/ru'
 "checksum rdrand 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "678054eb77286b51581ba43620cc911abf02758c91f93f479767aed0f90458b2"
 "checksum redox_syscall 0.1.56 (registry+https://github.com/rust-lang/crates.io-index)" = "2439c63f3f6139d1b57529d16bc3b8bb855230c8efcc5d3a896c8bea7c3b1e84"
 "checksum regex 1.3.4 (registry+https://github.com/rust-lang/crates.io-index)" = "322cf97724bea3ee221b78fe25ac9c46114ebb51747ad5babd51a2fc6a8235a8"
-"checksum regex-syntax 0.6.14 (registry+https://github.com/rust-lang/crates.io-index)" = "b28dfe3fe9badec5dbf0a79a9cccad2cfc2ab5484bdb3e44cbd1ae8b3ba2be06"
+"checksum regex-syntax 0.6.16 (registry+https://github.com/rust-lang/crates.io-index)" = "1132f845907680735a84409c3bebc64d1364a5683ffbce899550cd09d5eaefc1"
 "checksum remove_dir_all 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)" = "4a83fa3702a688b9359eccba92d153ac33fd2e8462f9e0e3fdf155239ea7792e"
 "checksum rustc_version 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)" = "138e3e0acb6c9fb258b19b67cb8abd63c00679d2851805ea151465464fe9030a"
 "checksum same-file 1.0.6 (registry+https://github.com/rust-lang/crates.io-index)" = "93fc1dc3aaa9bfed95e02e6eadabb4baf7e3078b0bd1b4d7b6b0b68378900502"
-"checksum scopeguard 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "b42e15e59b18a828bbf5c58ea01debb36b9b096346de35d941dcb89009f24a0d"
+"checksum scopeguard 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "d29ab0c6d3fc0ee92fe66e2d99f700eab17a8d57d1c1d3b748380fb20baa78cd"
 "checksum semver 0.9.0 (registry+https://github.com/rust-lang/crates.io-index)" = "1d7eb9ef2c18661902cc47e535f9bc51b78acd254da71d375c2f6720d9a40403"
 "checksum semver-parser 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)" = "388a1df253eca08550bef6c72392cfe7c30914bf41df5269b68cbd6ff8f570a3"
+"checksum simple_logger 1.6.0 (registry+https://github.com/rust-lang/crates.io-index)" = "fea0c4611f32f4c2bac73754f22dca1f57e6c1945e0590dae4e5f2a077b92367"
 "checksum strsim 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)" = "8ea5119cdb4c55b55d432abb513a0429384878c15dde60cc77b1c99de1a95a6a"
-"checksum syn 1.0.14 (registry+https://github.com/rust-lang/crates.io-index)" = "af6f3550d8dff9ef7dc34d384ac6f107e5d31c8f57d9f28e0081503f547ac8f5"
+"checksum syn 1.0.16 (registry+https://github.com/rust-lang/crates.io-index)" = "123bd9499cfb380418d509322d7a6d52e5315f064fe4b3ad18a53d6b92c07859"
 "checksum tempfile 3.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "7a6e24d9338a0a5be79593e2fa15a648add6138caa803e2d5bc782c371732ca9"
 "checksum textwrap 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)" = "d326610f408c7a4eb6f51c37c330e496b08506c9457c9d34287ecc38809fb060"
 "checksum thread_local 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)" = "d40c6d1b69745a6ec6fb1ca717914848da4b44ae29d9b3080cbee91d72a69b14"
+"checksum time 0.1.42 (registry+https://github.com/rust-lang/crates.io-index)" = "db8dcfca086c1143c9270ac42a2bbd8a7ee477b78ac8e45b19abfb0cbede4b6f"
 "checksum twox-hash 1.5.0 (registry+https://github.com/rust-lang/crates.io-index)" = "3bfd5b7557925ce778ff9b9ef90e3ade34c524b5ff10e239c69a42d546d2af56"
 "checksum unicode-width 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)" = "caaa9d531767d1ff2150b9332433f32a24622147e5ebb1f26409d5da67afd479"
 "checksum unicode-xid 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "826e7639553986605ec5979c7dd957c7895e93eabed50ab2ffa7f6128a75097c"

rust/hg-core/Cargo.toml

@@ -22,6 +22,7 b' regex = "1.1.0"'
 twox-hash = "1.5.0"
 same-file = "1.0.6"
 crossbeam = "0.7.3"
+log = "0.4.8"
 
 [dev-dependencies]
 clap = "*"

rust/hg-cpython/Cargo.toml

@@ -24,6 +24,7 b' python3-bin = ["cpython/python3-sys"]'
 [dependencies]
 hg-core = { path = "../hg-core"}
 libc = '*'
+simple_logger = "1.6.0"
 
 [dependencies.cpython]
 version = "0.4"

rust/hg-cpython/src/dirstate.rs

@@ -107,6 +107,8 b' pub fn init_module(py: Python, package: '
     let dotted_name = &format!("{}.dirstate", package);
     let m = PyModule::new(py, dotted_name)?;
 
+    simple_logger::init_by_env();
+
     m.add(py, "__package__", package)?;
     m.add(py, "__doc__", "Dirstate - Rust implementation")?;