Add nix search --all

src/nix/search.cc

@@ -25,8 +25,17 @@ struct CmdSearch : InstallableCommand, MixJSON
 {
     std::vector<std::string> res;
 
+    bool all = false;
+
     CmdSearch()
     {
+        addFlag({
+            .longName = "all",
+            .shortName = 'a',
+            .description = "Show all packages for a flake.",
+            .handler = {&all, true},
+        });
+
         expectArgs("regex", &res);
     }
 
@@ -55,11 +64,17 @@ struct CmdSearch : InstallableCommand, MixJSON
         settings.readOnlyMode = true;
         evalSettings.enableImportFromDerivation.setDefault(false);
 
-        // Empty search string should match all packages
-        // Use "^" here instead of ".*" due to differences in resulting highlighting
-        // (see #1893 -- libc++ claims empty search string is not in POSIX grammar)
-        if (res.empty())
-            res.push_back("^");
+        if (all) {
+            // Use "^" here instead of ".*" due to differences in resulting highlighting
+            // (see #1893 -- libc++ claims empty search string is not in POSIX grammar)
+            if (res.empty())
+                res.push_back("^");
+            else
+                throw Error("'--all' does not expect a search term");
+        } else {
+            if (res.empty())
+                throw Error("search term cannot be empty");
+        }
 
         std::vector<std::regex> regexes;
         regexes.reserve(res.size());

src/nix/search.md

@@ -5,7 +5,7 @@ R""(
 * Show all packages in the `nixpkgs` flake:
 
   ```console
-  # nix search nixpkgs
+  # nix search -a nixpkgs
   * legacyPackages.x86_64-linux.AMB-plugins (0.8.1)
     A set of ambisonics ladspa plugins
 
@@ -34,7 +34,7 @@ R""(
 * Show all packages in the flake in the current directory:
 
   ```console
-  # nix search
+  # nix search -a
   ```
 
 * Search for Firefox or Chromium:
@@ -56,8 +56,7 @@ flake) for packages whose name or description matches all of the
 regular expressions *regex*.  For each matching package, It prints the
 full attribute name (from the root of the installable), the version
 and the `meta.description` field, highlighting the substrings that
-were matched by the regular expressions. If no regular expressions are
-specified, all packages are shown.
+were matched by the regular expressions.
 
 # Flake output attributes
 

tests/search.sh

@@ -19,10 +19,10 @@ clearCache
 
 ## Search expressions
 
-# Check that empty search string matches all
-nix search -f search.nix '' |grep -q foo
-nix search -f search.nix '' |grep -q bar
-nix search -f search.nix '' |grep -q hello
+# Check that '--all' flag matches all
+nix search -af search.nix |grep -q foo
+nix search --all -f search.nix |grep -q bar
+nix search -af search.nix |grep -q hello
 
 ## Tests for multiple regex/match highlighting