Add apt generator for available repo packages (#207)

Author: lucieleblanc

command-signatures/json/apt-get.json

@@ -55,7 +55,7 @@
             "args": {
                 "generatorName": [
                     "list_all_deb_files_in_cwd",
-                    "list_all_packages"
+                    "list_available_packages"
                 ]
             },
             "isVariadic": true,

command-signatures/json/aptitude.json

@@ -25,7 +25,7 @@
             "args": {
                 "generatorName": [
                     "list_all_deb_files_in_cwd",
-                    "list_all_packages"
+                    "list_available_packages"
                 ]
             },
             "isVariadic": true,

command-signatures/src/generators/apt.rs

@@ -7,6 +7,9 @@ use warp_completion_metadata::{
 const LIST_ALL_PACKAGES_NAME: &str = "list_all_packages";
 const LIST_ALL_PACKAGES_COMMAND: &str = r#"dpkg-query --show --showformat '${Package}\n'"#;
 
+const LIST_AVAILABLE_PACKAGES_NAME: &str = "list_available_packages";
+const LIST_AVAILABLE_PACKAGES_COMMAND: &str = "apt-cache pkgnames";
+
 const LIST_ALL_DEB_FILES_NAME: &str = "list_all_deb_files_in_cwd";
 const LIST_ALL_DEB_FILES_COMMAND: &str = r#"find . -maxdepth 1 -type f -name '*.deb'"#;
 
@@ -21,6 +24,19 @@ pub fn list_all_packages(output: &str) -> GeneratorResults {
     targets.into_iter().collect_unordered_results()
 }
 
+pub fn list_available_packages(output: &str) -> GeneratorResults {
+    let mut targets = Vec::new();
+    for package_name in output.lines() {
+        if !package_name.is_empty() {
+            targets.push(Suggestion::with_description(
+                package_name.to_string(),
+                "package",
+            ));
+        }
+    }
+    targets.into_iter().collect_unordered_results()
+}
+
 pub fn list_all_deb_files_in_cwd(output: &str) -> GeneratorResults {
     let mut targets = Vec::new();
     for file in output.lines() {
@@ -42,6 +58,13 @@ pub fn apt_get_generators() -> CommandSignatureGenerators {
                 list_all_packages,
             ),
         )
+        .add_generator(
+            LIST_AVAILABLE_PACKAGES_NAME,
+            Generator::script(
+                CommandBuilder::single_command(LIST_AVAILABLE_PACKAGES_COMMAND),
+                list_available_packages,
+            ),
+        )
         .add_generator(
             LIST_ALL_DEB_FILES_NAME,
             Generator::script(
@@ -60,6 +83,13 @@ pub fn aptitude_generators() -> CommandSignatureGenerators {
                 list_all_packages,
             ),
         )
+        .add_generator(
+            LIST_AVAILABLE_PACKAGES_NAME,
+            Generator::script(
+                CommandBuilder::single_command(LIST_AVAILABLE_PACKAGES_COMMAND),
+                list_available_packages,
+            ),
+        )
         .add_generator(
             LIST_ALL_DEB_FILES_NAME,
             Generator::script(