fix: Show Java version from OpenJ9 Java runtimes (#507)

This PR tries to improve the version detection across multiple Java VM vendors. The module captures both STDOUT and STDERR outputs of the java -Xinternalversion call.

Eclipse OpenJ9, Azul Zulu, SapMachine, Amazon Corretto and GraalVM outputs are unit tested now.

6 files changed, 159 insertions, 19 deletions

diff --git a/Cargo.lock b/Cargo.lock
index 5f8131d69..720936818 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -376,6 +376,18 @@ version = "1.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
+name = "lexical-core"
+version = "0.4.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "arrayvec 0.4.11 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cfg-if 0.1.10 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc_version 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "ryu 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "static_assertions 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
 name = "libc"
 version = "0.2.62"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -459,6 +471,16 @@ version = "0.1.13"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
+name = "nom"
+version = "5.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "lexical-core 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "memchr 2.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "version_check 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
 name = "num-integer"
 version = "0.1.41"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -767,6 +789,7 @@ dependencies = [
  "gethostname 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "git2 0.10.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.4.8 (registry+https://github.com/rust-lang/crates.io-index)",
+ "nom 5.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "once_cell 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "path-slash 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "pretty_env_logger 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -790,6 +813,11 @@ dependencies = [
 ]
 
 [[package]]
+name = "static_assertions"
+version = "0.3.4"
+source = "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"
@@ -963,6 +991,11 @@ version = "0.8.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
+name = "version_check"
+version = "0.1.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
 name = "void"
 version = "1.0.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -1062,6 +1095,7 @@ dependencies = [
 "checksum jobserver 0.1.17 (registry+https://github.com/rust-lang/crates.io-index)" = "f2b1d42ef453b30b7387e113da1c83ab1605d90c5b4e0eb8e96d016ed3b8c160"
 "checksum lazy_static 1.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "e2abad23fbc42b3700f2f279844dc832adb2b2eb069b2df918f455c4e18cc646"
 "checksum lazycell 1.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "b294d6fa9ee409a054354afc4352b0b9ef7ca222c69b8812cbea9e7d2bf3783f"
+"checksum lexical-core 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)" = "2304bccb228c4b020f3a4835d247df0a02a7c4686098d4167762cfbbe4c5cb14"
 "checksum libc 0.2.62 (registry+https://github.com/rust-lang/crates.io-index)" = "34fcd2c08d2f832f376f4173a231990fa5aef4e99fb569867318a227ef4c06ba"
 "checksum libgit2-sys 0.9.1 (registry+https://github.com/rust-lang/crates.io-index)" = "a30f8637eb59616ee3b8a00f6adff781ee4ddd8343a615b8238de756060cc1b3"
 "checksum libz-sys 1.0.25 (registry+https://github.com/rust-lang/crates.io-index)" = "2eb5e43362e38e2bca2fd5f5134c4d4564a23a5c28e9b95411652021a8675ebe"
@@ -1073,6 +1107,7 @@ dependencies = [
 "checksum memoffset 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)" = "ce6075db033bbbb7ee5a0bbd3a3186bbae616f57fb001c485c7ff77955f8177f"
 "checksum nix 0.14.1 (registry+https://github.com/rust-lang/crates.io-index)" = "6c722bee1037d430d0f8e687bbdbf222f27cc6e4e68d5caf630857bb2b6dbdce"
 "checksum nodrop 0.1.13 (registry+https://github.com/rust-lang/crates.io-index)" = "2f9667ddcc6cc8a43afc9b7917599d7216aa09c463919ea32c59ed6cac8bc945"
+"checksum nom 5.0.1 (registry+https://github.com/rust-lang/crates.io-index)" = "c618b63422da4401283884e6668d39f819a106ef51f5f59b81add00075da35ca"
 "checksum num-integer 0.1.41 (registry+https://github.com/rust-lang/crates.io-index)" = "b85e541ef8255f6cf42bbfe4ef361305c6c135d10919ecc26126c4e5ae94bc09"
 "checksum num-traits 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)" = "6ba9a427cfca2be13aa6f6403b0b7e7368fe982bfa16fccc450ce74c46cd9b32"
 "checksum num_cpus 1.10.1 (registry+https://github.com/rust-lang/crates.io-index)" = "bcef43580c035376c0705c42792c294b66974abbfd2789b511784023f71f3273"
@@ -1112,6 +1147,7 @@ dependencies = [
 "checksum serde 1.0.101 (registry+https://github.com/rust-lang/crates.io-index)" = "9796c9b7ba2ffe7a9ce53c2287dfc48080f4b2b362fcc245a259b3a7201119dd"
 "checksum serde_json 1.0.41 (registry+https://github.com/rust-lang/crates.io-index)" = "2f72eb2a68a7dc3f9a691bfda9305a1c017a6215e5a4545c258500d2099a37c2"
 "checksum smallvec 0.6.10 (registry+https://github.com/rust-lang/crates.io-index)" = "ab606a9c5e214920bb66c458cd7be8ef094f813f20fe77a54cc7dbfff220d4b7"
+"checksum static_assertions 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)" = "7f3eb36b47e512f8f1c9e3d10c2c1965bc992bd9cdb024fa581e2194501c83d3"
 "checksum strsim 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)" = "8ea5119cdb4c55b55d432abb513a0429384878c15dde60cc77b1c99de1a95a6a"
 "checksum syn 0.15.44 (registry+https://github.com/rust-lang/crates.io-index)" = "9ca4b3b69a77cbe1ffc9e198781b7acb0c7365a883670e8f1c1bc66fba79a5c5"
 "checksum syn 1.0.5 (registry+https://github.com/rust-lang/crates.io-index)" = "66850e97125af79138385e9b88339cbcd037e3f28ceab8c5ad98e64f0f1f80bf"
@@ -1134,6 +1170,7 @@ dependencies = [
 "checksum url 2.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "75b414f6c464c879d7f9babf951f23bc3743fb7313c081b2e6ca719067ea9d61"
 "checksum vcpkg 0.2.7 (registry+https://github.com/rust-lang/crates.io-index)" = "33dd455d0f96e90a75803cfeb7f948768c08d70a6de9a8d2362461935698bf95"
 "checksum vec_map 0.8.1 (registry+https://github.com/rust-lang/crates.io-index)" = "05c78687fb1a80548ae3250346c3db86a80a7cdd77bda190189f2d0a0987c81a"
+"checksum version_check 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)" = "914b1a6776c4c929a602fafd8bc742e06365d4bcbe48c30f9cca5824f70dc9dd"
 "checksum void 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)" = "6a02e4885ed3bc0f2de90ea6dd45ebcbb66dacffe03547fadbb0eeae2770887d"
 "checksum wasi 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)" = "b89c3ce4ce14bdc6fb6beaf9ec7928ca331de5df7e5ea278375642a2f478570d"
 "checksum winapi 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)" = "8093091eeb260906a183e6ae1abdba2ef5ef2257a21801128899c3fc699229c6"
diff --git a/Cargo.toml b/Cargo.toml
index c6b258d41..b54f60ede 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -45,6 +45,7 @@ sysinfo = "0.9.5"
 byte-unit = "3.0.3"
 starship_module_config_derive = { version = "0.1.0", path = "starship_module_config_derive" }
 yaml-rust = "0.4"
+nom = "5.0.1"
 
 [dev-dependencies]
 tempfile = "3.1.0"
diff --git a/src/modules/java.rs b/src/modules/java.rs
index bd4e3c807..80c25747d 100644
--- a/src/modules/java.rs
+++ b/src/modules/java.rs
@@ -1,9 +1,12 @@
 use std::process::Command;
+use std::process::Output;
 
 use ansi_term::Color;
 
 use super::{Context, Module};
 
+use crate::modules::utils::java_version_parser;
+
 /// Creates a module with the current Java version
 ///
 /// Will display the Java version if any of the following criteria are met:
@@ -47,27 +50,24 @@ fn get_java_version() -> Option<String> {
     };
 
     match Command::new(java_command).arg("-Xinternalversion").output() {
-        Ok(output) => Some(String::from_utf8(output.stdout).unwrap()),
+        Ok(output) => Some(combine_outputs(output)),
         Err(_) => None,
     }
 }
 
-/// Extract the java version from `java_stdout`.
-/// The expected format is similar to: "JRE (1.8.0_222-b10)".
-/// Some Java vendors don't follow this format: "JRE (Zulu 8.40.0.25-CA-linux64)").
-fn format_java_version(java_stdout: String) -> Option<String> {
-    let start = java_stdout.find("JRE (")? + "JRE (".len();
-    let end = start
-        + (java_stdout[start..].find(|c| match c {
-            '0'..='9' | '.' => false,
-            _ => true,
-        })?);
-
-    if start == end {
-        None
-    } else {
-        Some(format!("v{}", &java_stdout[start..end]))
-    }
+/// Combines the standard and error outputs.
+///
+/// This is due some Java vendors using `STDERR` as the output.
+fn combine_outputs(output: Output) -> String {
+    let std_out = String::from_utf8(output.stdout).unwrap();
+    let std_err = String::from_utf8(output.stderr).unwrap();
+
+    format!("{}{}", std_out, std_err)
+}
+
+/// Extract the java version from `java_out`.
+fn format_java_version(java_out: String) -> Option<String> {
+    java_version_parser::parse_jre_version(&java_out).map(|result| format!("v{}", result))
 }
 
 #[cfg(test)]
@@ -98,8 +98,43 @@ mod tests {
 
     #[test]
     fn test_format_java_version_zulu() {
-        // Not currently supported
         let java_8 = String::from("OpenJDK 64-Bit Server VM (25.222-b10) for linux-amd64 JRE (Zulu 8.40.0.25-CA-linux64) (1.8.0_222-b10), built on Jul 11 2019 11:36:39 by \"zulu_re\" with gcc 4.4.7 20120313 (Red Hat 4.4.7-3)");
-        assert_eq!(format_java_version(java_8), None);
+        let java_11 = String::from("OpenJDK 64-Bit Server VM (11.0.4+11-LTS) for linux-amd64 JRE (Zulu11.33+15-CA) (11.0.4+11-LTS), built on Jul 11 2019 21:37:17 by \"zulu_re\" with gcc 4.9.2 20150212 (Red Hat 4.9.2-6)");
+        assert_eq!(format_java_version(java_8), Some(String::from("v1.8.0")));
+        assert_eq!(format_java_version(java_11), Some(String::from("v11.0.4")));
+    }
+
+    #[test]
+    fn test_format_java_version_eclipse_openj9() {
+        let java_8 = String::from("Eclipse OpenJ9 OpenJDK 64-bit Server VM (1.8.0_222-b10) from linux-amd64 JRE with Extensions for OpenJDK for Eclipse OpenJ9 8.0.222.0, built on Jul 17 2019 21:29:18 by jenkins with g++ (GCC) 7.3.1 20180303 (Red Hat 7.3.1-5)");
+        let java_11 = String::from("Eclipse OpenJ9 OpenJDK 64-bit Server VM (11.0.4+11) from linux-amd64 JRE with Extensions for OpenJDK for Eclipse OpenJ9 11.0.4.0, built on Jul 17 2019 21:51:37 by jenkins with g++ (GCC) 7.3.1 20180303 (Red Hat 7.3.1-5)");
+        assert_eq!(format_java_version(java_8), Some(String::from("v1.8.0")));
+        assert_eq!(format_java_version(java_11), Some(String::from("v11.0.4")));
+    }
+
+    #[test]
+    fn test_format_java_version_graalvm() {
+        let java_8 = String::from("OpenJDK 64-Bit GraalVM CE 19.2.0.1 (25.222-b08-jvmci-19.2-b02) for linux-amd64 JRE (8u222), built on Jul 19 2019 17:37:13 by \"buildslave\" with gcc 7.3.0");
+        assert_eq!(format_java_version(java_8), Some(String::from("v8")));
+    }
+
+    #[test]
+    fn test_format_java_version_amazon_corretto() {
+        let java_8 = String::from("OpenJDK 64-Bit Server VM (25.222-b10) for linux-amd64 JRE (1.8.0_222-b10), built on Jul 11 2019 20:48:53 by \"root\" with gcc 7.3.1 20180303 (Red Hat 7.3.1-5)");
+        let java_11 = String::from("OpenJDK 64-Bit Server VM (11.0.4+11-LTS) for linux-amd64 JRE (11.0.4+11-LTS), built on Jul 11 2019 20:06:11 by \"\" with gcc 7.3.1 20180303 (Red Hat 7.3.1-5)");
+        assert_eq!(format_java_version(java_8), Some(String::from("v1.8.0")));
+        assert_eq!(format_java_version(java_11), Some(String::from("v11.0.4")));
+    }
+
+    #[test]
+    fn test_format_java_version_sapmachine() {
+        let java_11 = String::from("OpenJDK 64-Bit Server VM (11.0.4+11-LTS-sapmachine) for linux-amd64 JRE (11.0.4+11-LTS-sapmachine), built on Jul 17 2019 08:58:43 by \"\" with gcc 7.3.0");
+        assert_eq!(format_java_version(java_11), Some(String::from("v11.0.4")));
+    }
+
+    #[test]
+    fn test_format_java_version_unknown() {
+        let unknown_jre = String::from("Unknown JRE");
+        assert_eq!(format_java_version(unknown_jre), None);
     }
 }
diff --git a/src/modules/mod.rs b/src/modules/mod.rs
index f32e6fcc0..e32af5c88 100644
--- a/src/modules/mod.rs
+++ b/src/modules/mod.rs
@@ -24,6 +24,7 @@ mod ruby;
 mod rust;
 mod time;
 mod username;
+mod utils;
 
 #[cfg(feature = "battery")]
 mod battery;
diff --git a/src/modules/utils/java_version_parser.rs b/src/modules/utils/java_version_parser.rs
new file mode 100644
index 000000000..cf9445dfe
--- /dev/null
+++ b/src/modules/utils/java_version_parser.rs
@@ -0,0 +1,65 @@
+use nom::{
+    branch::alt,
+    bytes::complete::{tag, take_until, take_while1},
+    combinator::rest,
+    sequence::{preceded, tuple},
+    IResult,
+};
+
+fn is_version(c: char) -> bool {
+    c >= '0' && c <= '9' || c == '.'
+}
+
+fn version(input: &str) -> IResult<&str, &str> {
+    take_while1(&is_version)(input)
+}
+
+fn zulu(input: &str) -> IResult<&str, &str> {
+    let zulu_prefix_value = preceded(take_until("("), tag("("));
+    preceded(zulu_prefix_value, version)(input)
+}
+
+fn jre_prefix(input: &str) -> IResult<&str, &str> {
+    preceded(take_until("JRE ("), tag("JRE ("))(input)
+}
+
+fn j9_prefix(input: &str) -> IResult<&str, &str> {
+    preceded(take_until("VM ("), tag("VM ("))(input)
+}
+
+fn suffix(input: &str) -> IResult<&str, &str> {
+    rest(input)
+}
+
+fn parse(input: &str) -> IResult<&str, &str> {
+    let prefix = alt((jre_prefix, j9_prefix));
+    let version_or_zulu = alt((version, zulu));
+    let (input, (_, version, _)) = tuple((prefix, version_or_zulu, suffix))(input)?;
+
+    Ok((input, version))
+}
+
+/// Parse the java version from `java -Xinternalversion` format.
+///
+/// The expected format is similar to:
+///     "JRE (1.8.0_222-b10)"
+///     "JRE (Zulu 8.40.0.25-CA-linux64) (1.8.0_222-b10)"
+///     "VM (1.8.0_222-b10)".
+///
+/// Some Java vendors might not follow this format.
+pub fn parse_jre_version(input: &str) -> Option<&str> {
+    parse(input).map(|result| result.1).ok()
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_parse_eclipse_openj9() {
+        let java_8 = "Eclipse OpenJ9 OpenJDK 64-bit Server VM (1.8.0_222-b10) from linux-amd64 JRE with Extensions for OpenJDK for Eclipse OpenJ9 8.0.222.0, built on Jul 17 2019 21:29:18 by jenkins with g++ (GCC) 7.3.1 20180303 (Red Hat 7.3.1-5)";
+        let java_11 = "Eclipse OpenJ9 OpenJDK 64-bit Server VM (11.0.4+11) from linux-amd64 JRE with Extensions for OpenJDK for Eclipse OpenJ9 11.0.4.0, built on Jul 17 2019 21:51:37 by jenkins with g++ (GCC) 7.3.1 20180303 (Red Hat 7.3.1-5)";
+        assert_eq!(parse(java_8), Ok(("", "1.8.0")));
+        assert_eq!(parse(java_11), Ok(("", "11.0.4")));
+    }
+}
diff --git a/src/modules/utils/mod.rs b/src/modules/utils/mod.rs
new file mode 100644
index 000000000..9e69310b2
--- /dev/null
+++ b/src/modules/utils/mod.rs
@@ -0,0 +1 @@
+pub mod java_version_parser;