mkDevShell: extract shell hooks

4 files changed, 54 insertions, 43 deletions

diff --git a/flake.nix b/flake.nix
index 3b09a54..d4cb882 100644
--- a/flake.nix
+++ b/flake.nix
@@ -3,8 +3,9 @@
 
   outputs = { self }: {
     lib = {
-      mkDevShell = import ./lib/mk-dev-shell.nix;
-      mkSandboxSystem = import ./lib/mk-sandbox-system.nix;
+      shell = import ./lib/shell.nix self;
+      mkDevShell = import ./lib/mk-dev-shell.nix self;
+      mkSandboxSystem = import ./lib/mk-sandbox-system.nix self;
     };
   };
 }
diff --git a/lib/mk-dev-shell.nix b/lib/mk-dev-shell.nix
index 87b9dbb..4f46d69 100644
--- a/lib/mk-dev-shell.nix
+++ b/lib/mk-dev-shell.nix
@@ -1,58 +1,23 @@
+flake:
 { pkgs
 , tools ? []
 , envVars ? {}
 , shell ? null
 }:
 
-with pkgs.lib;
-
 let
-  mapAttrsToLines = mapping: attrs:
-    pkgs.lib.concatStringsSep "\n" (pkgs.lib.mapAttrsToList mapping attrs);
-
-  exportEnvVar = k: v: ''
-    export ${escapeShellArg k}="${v}"
-  '';
-
-  exportEnvVarsHook = mapAttrsToLines exportEnvVar;
-
-  fmt = rec {
-    codeBlock = code: text: ''"\e[${code}m"${text}"\e[0m"'';
-    keyword = codeBlock "1;36";
-    section = codeBlock "4;35";
-    printSectionTitle = title: ''echo -e "\n\n"${section title}"\n"'';
-  };
-
-  printEnvVar = k: v: ''
-    echo -e ${fmt.keyword (escapeShellArg "$" + k)}: ${escapeShellArg v}
-  '';
-
-  printEnvVarsHook = envVars: ''
-    ${fmt.printSectionTitle "DEVSHELL ENVIRONMENT VARIABLES"}
-    ${mapAttrsToLines printEnvVar envVars}
-  '';
-
-  printToolsHook = tools: ''
-    ${fmt.printSectionTitle "DEVSHELL TOOLS"}
-    ls "${pkgs.symlinkJoin { name = "env"; paths = tools; }}/bin"
-  '';
-
-  # Use the default user shell instead of Bash
-  startUserShellHook = ''
-    $(${pkgs.finger_bsd}/bin/finger $USER \
-      | ${pkgs.gnugrep}/bin/grep -oP 'Shell: \K.*')
-  '';
+  shellLib = flake.lib.shell { inherit pkgs; };
 
 in pkgs.mkShell {
   packages = tools;
   shellHook = ''
-    ${exportEnvVarsHook envVars}
+    ${shellLib.exportEnvVars envVars}
 
-    ${optionalString (envVars != {}) (printEnvVarsHook envVars)}
-    ${optionalString (tools != []) (printToolsHook tools)}
+    ${pkgs.lib.optionalString (envVars != {}) (shellLib.printEnvVars envVars)}
+    ${pkgs.lib.optionalString (tools != []) (shellLib.printBins tools)}
     echo
 
-    ${if (shell != null) then shell else startUserShellHook}
+    ${if (shell != null) then shell else shellLib.startUserShell}
     exit $?
   '';
 }
diff --git a/lib/mk-sandbox-system.nix b/lib/mk-sandbox-system.nix
index b2d85e2..a56bdab 100644
--- a/lib/mk-sandbox-system.nix
+++ b/lib/mk-sandbox-system.nix
@@ -1,3 +1,4 @@
+flake:
 { pkgs
 , name ? "sandbox"
 , user ? "dummy"
diff --git a/lib/shell.nix b/lib/shell.nix
new file mode 100644
index 0000000..3f6defc
--- /dev/null
+++ b/lib/shell.nix
@@ -0,0 +1,44 @@
+flake:
+{ pkgs
+}:
+
+with pkgs.lib;
+
+let
+  mapAttrsToLines = mapping: attrs:
+    pkgs.lib.concatStringsSep "\n" (pkgs.lib.mapAttrsToList mapping attrs);
+
+  fmt = rec {
+    codeBlock = code: text: ''"\e[${code}m"${text}"\e[0m"'';
+    keyword = codeBlock "1;36";
+    section = codeBlock "4;35";
+    printSectionTitle = title: ''echo -e "\n\n"${section title}"\n"'';
+  };
+
+in rec {
+  exportEnvVar = k: v: ''
+    export ${escapeShellArg k}="${v}"
+  '';
+
+  exportEnvVars = mapAttrsToLines exportEnvVar;
+
+  printEnvVar = k: v: ''
+    echo -e ${fmt.keyword (escapeShellArg "$" + k)}: ${escapeShellArg v}
+  '';
+
+  printEnvVars = envVars: ''
+    ${fmt.printSectionTitle "ENVIRONMENT VARIABLES"}
+    ${mapAttrsToLines printEnvVar envVars}
+  '';
+
+  printBins = packagePaths: ''
+    ${fmt.printSectionTitle "TOOLS"}
+    ls "${pkgs.symlinkJoin { name = "env"; paths = packagePaths; }}/bin"
+  '';
+
+  # Use the default user shell instead of Bash
+  startUserShell = ''
+    $(${pkgs.finger_bsd}/bin/finger $USER \
+      | ${pkgs.gnugrep}/bin/grep -oP 'Shell: \K.*')
+  '';
+}