From d1dc8384cab7ef1bf0a79510295c1e91da0556ff Mon Sep 17 00:00:00 2001
From: Robert Hensing <robert@roberthensing.nl>
Date: Wed, 26 Jul 2023 13:46:42 +0200
Subject: [PATCH 1/4] writeCBin: Add meta.mainProgram

... and add tests.
---
 .../trivial-builders/default.nix              |  9 +++-
 .../trivial-builders/test/writeCBin.nix       | 43 +++++++++++++++++++
 .../trivial-builders/test/writeScriptBin.nix  | 39 +++++++++++++++++
 .../test/writeShellScriptBin.nix              | 39 +++++++++++++++++
 pkgs/test/default.nix                         |  3 ++
 5 files changed, 132 insertions(+), 1 deletion(-)
 create mode 100644 pkgs/build-support/trivial-builders/test/writeCBin.nix
 create mode 100644 pkgs/build-support/trivial-builders/test/writeScriptBin.nix
 create mode 100644 pkgs/build-support/trivial-builders/test/writeShellScriptBin.nix

diff --git a/pkgs/build-support/trivial-builders/default.nix b/pkgs/build-support/trivial-builders/default.nix
index 9099a38b75b3..d095974513cb 100644
--- a/pkgs/build-support/trivial-builders/default.nix
+++ b/pkgs/build-support/trivial-builders/default.nix
@@ -242,7 +242,11 @@ rec {
 
 
   */
-  writeScriptBin = name: text: writeTextFile {inherit name text; executable = true; destination = "/bin/${name}";};
+  writeScriptBin = name: text: writeTextFile {
+    inherit name text;
+    executable = true;
+    destination = "/bin/${name}";
+  };
 
   /*
     Similar to writeScript. Writes a Shell script and checks its syntax.
@@ -374,6 +378,9 @@ rec {
       # Pointless to do this on a remote machine.
       preferLocalBuild = true;
       allowSubstitutes = false;
+      meta = {
+        mainProgram = name;
+      };
     }
     ''
       n=$out/bin/$name
diff --git a/pkgs/build-support/trivial-builders/test/writeCBin.nix b/pkgs/build-support/trivial-builders/test/writeCBin.nix
new file mode 100644
index 000000000000..56cab45b3801
--- /dev/null
+++ b/pkgs/build-support/trivial-builders/test/writeCBin.nix
@@ -0,0 +1,43 @@
+/*
+  Run with:
+
+      cd nixpkgs
+      nix-build -A tests.trivial-builders.writeCBin
+*/
+
+{ lib, writeCBin, runCommand }:
+let
+  output = "hello";
+  pkg = writeCBin "test-script" ''
+    #include <stdio.h>
+    int main () {
+      printf("hello\n");
+      return 0;
+    }
+  '';
+in
+  assert pkg.meta.mainProgram == "test-script";
+  runCommand "test-writeCBin" { } ''
+
+    echo Testing with getExe...
+
+    target=${lib.getExe pkg}
+    expected=${lib.escapeShellArg output}
+    got=$("$target")
+    if [[ "$got" != "$expected" ]]; then
+      echo "wrong output: expected $expected, got $got"
+      exit 1
+    fi
+
+    echo Testing with makeBinPath...
+
+    PATH="${lib.makeBinPath [ pkg ]}:$PATH"
+    got=$(test-script)
+    if [[ "$got" != "$expected" ]]; then
+      echo "wrong output: expected $expected, got $got"
+      exit 1
+    fi
+
+    touch $out
+  ''
+
diff --git a/pkgs/build-support/trivial-builders/test/writeScriptBin.nix b/pkgs/build-support/trivial-builders/test/writeScriptBin.nix
new file mode 100644
index 000000000000..1487443130da
--- /dev/null
+++ b/pkgs/build-support/trivial-builders/test/writeScriptBin.nix
@@ -0,0 +1,39 @@
+/*
+  Run with:
+
+      cd nixpkgs
+      nix-build -A tests.trivial-builders.writeShellScriptBin
+*/
+
+{ lib, writeScriptBin, runCommand }:
+let
+  output = "hello";
+  pkg = writeScriptBin "test-script" ''
+    echo ${lib.escapeShellArg output}
+  '';
+in
+  assert pkg.meta.mainProgram == "test-script";
+  runCommand "test-writeScriptBin" { } ''
+
+    echo Testing with getExe...
+
+    target=${lib.getExe pkg}
+    expected=${lib.escapeShellArg output}
+    got=$("$target")
+    if [[ "$got" != "$expected" ]]; then
+      echo "wrong output: expected $expected, got $got"
+      exit 1
+    fi
+
+    echo Testing with makeBinPath...
+
+    PATH="${lib.makeBinPath [ pkg ]}:$PATH"
+    got=$(test-script)
+    if [[ "$got" != "$expected" ]]; then
+      echo "wrong output: expected $expected, got $got"
+      exit 1
+    fi
+
+    touch $out
+  ''
+
diff --git a/pkgs/build-support/trivial-builders/test/writeShellScriptBin.nix b/pkgs/build-support/trivial-builders/test/writeShellScriptBin.nix
new file mode 100644
index 000000000000..e93410e25bcb
--- /dev/null
+++ b/pkgs/build-support/trivial-builders/test/writeShellScriptBin.nix
@@ -0,0 +1,39 @@
+/*
+  Run with:
+
+      cd nixpkgs
+      nix-build -A tests.trivial-builders.writeShellScriptBin
+*/
+
+{ lib, writeShellScriptBin, runCommand }:
+let
+  output = "hello";
+  pkg = writeShellScriptBin "test-script" ''
+    echo ${lib.escapeShellArg output}
+  '';
+in
+  assert pkg.meta.mainProgram == "test-script";
+  runCommand "test-writeShellScriptBin" { } ''
+
+    echo Testing with getExe...
+
+    target=${lib.getExe pkg}
+    expected=${lib.escapeShellArg output}
+    got=$("$target")
+    if [[ "$got" != "$expected" ]]; then
+      echo "wrong output: expected $expected, got $got"
+      exit 1
+    fi
+
+    echo Testing with makeBinPath...
+
+    PATH="${lib.makeBinPath [ pkg ]}:$PATH"
+    got=$(test-script)
+    if [[ "$got" != "$expected" ]]; then
+      echo "wrong output: expected $expected, got $got"
+      exit 1
+    fi
+
+    touch $out
+  ''
+
diff --git a/pkgs/test/default.nix b/pkgs/test/default.nix
index b6793d25b6e2..141b4c67fbeb 100644
--- a/pkgs/test/default.nix
+++ b/pkgs/test/default.nix
@@ -67,9 +67,12 @@ with pkgs;
   cuda = callPackage ./cuda { };
 
   trivial-builders = recurseIntoAttrs {
+    writeCBin = callPackage ../build-support/trivial-builders/test/writeCBin.nix {};
+    writeScriptBin = callPackage ../build-support/trivial-builders/test/writeScriptBin.nix {};
     writeStringReferencesToFile = callPackage ../build-support/trivial-builders/test/writeStringReferencesToFile.nix {};
     writeTextFile = callPackage ../build-support/trivial-builders/test/write-text-file.nix {};
     writeShellScript = callPackage ../build-support/trivial-builders/test/write-shell-script.nix {};
+    writeShellScriptBin = callPackage ../build-support/trivial-builders/test/writeShellScriptBin.nix {};
     references = callPackage ../build-support/trivial-builders/test/references.nix {};
     overriding = callPackage ../build-support/trivial-builders/test-overriding.nix {};
     concat = callPackage ../build-support/trivial-builders/test/concat-test.nix {};

From 89bdfd468735de3c526da5203d3a6731b1a285d1 Mon Sep 17 00:00:00 2001
From: Robert Hensing <robert@roberthensing.nl>
Date: Wed, 26 Jul 2023 13:51:47 +0200
Subject: [PATCH 2/4] trivial-builders: Move test list closer

---
 .../trivial-builders/test/default.nix         | 29 +++++++++++++++++++
 pkgs/test/default.nix                         | 13 +--------
 2 files changed, 30 insertions(+), 12 deletions(-)
 create mode 100644 pkgs/build-support/trivial-builders/test/default.nix

diff --git a/pkgs/build-support/trivial-builders/test/default.nix b/pkgs/build-support/trivial-builders/test/default.nix
new file mode 100644
index 000000000000..cde2014b5adc
--- /dev/null
+++ b/pkgs/build-support/trivial-builders/test/default.nix
@@ -0,0 +1,29 @@
+/*
+  Run all tests with:
+
+      cd nixpkgs
+      nix-build -A tests.trivial-builders
+
+  or run a specific test with:
+
+      cd nixpkgs
+      nix-build -A tests.trivial-builders.foo
+
+*/
+
+{ callPackage, lib }:
+let
+  inherit (lib) recurseIntoAttrs;
+in
+recurseIntoAttrs {
+  concat = callPackage ./concat-test.nix {};
+  linkFarm = callPackage ./link-farm.nix {};
+  overriding = callPackage ../test-overriding.nix {};
+  references = callPackage ./references.nix {};
+  writeCBin = callPackage ./writeCBin.nix {};
+  writeScriptBin = callPackage ./writeScriptBin.nix {};
+  writeShellScript = callPackage ./write-shell-script.nix {};
+  writeShellScriptBin = callPackage ./writeShellScriptBin.nix {};
+  writeStringReferencesToFile = callPackage ./writeStringReferencesToFile.nix {};
+  writeTextFile = callPackage ./write-text-file.nix {};
+}
diff --git a/pkgs/test/default.nix b/pkgs/test/default.nix
index 141b4c67fbeb..6bfa1c4393c4 100644
--- a/pkgs/test/default.nix
+++ b/pkgs/test/default.nix
@@ -66,18 +66,7 @@ with pkgs;
 
   cuda = callPackage ./cuda { };
 
-  trivial-builders = recurseIntoAttrs {
-    writeCBin = callPackage ../build-support/trivial-builders/test/writeCBin.nix {};
-    writeScriptBin = callPackage ../build-support/trivial-builders/test/writeScriptBin.nix {};
-    writeStringReferencesToFile = callPackage ../build-support/trivial-builders/test/writeStringReferencesToFile.nix {};
-    writeTextFile = callPackage ../build-support/trivial-builders/test/write-text-file.nix {};
-    writeShellScript = callPackage ../build-support/trivial-builders/test/write-shell-script.nix {};
-    writeShellScriptBin = callPackage ../build-support/trivial-builders/test/writeShellScriptBin.nix {};
-    references = callPackage ../build-support/trivial-builders/test/references.nix {};
-    overriding = callPackage ../build-support/trivial-builders/test-overriding.nix {};
-    concat = callPackage ../build-support/trivial-builders/test/concat-test.nix {};
-    linkFarm = callPackage ../build-support/trivial-builders/test/link-farm.nix {};
-  };
+  trivial-builders = callPackage ../build-support/trivial-builders/test/default.nix {};
 
   writers = callPackage ../build-support/writers/test.nix {};
 

From a6aabd9d28ea935072b4825bbc15ef7cc40e5e36 Mon Sep 17 00:00:00 2001
From: Robert Hensing <robert@roberthensing.nl>
Date: Wed, 26 Jul 2023 14:26:43 +0200
Subject: [PATCH 3/4] tests.trivial-builders.references: Only run where
 supported

---
 pkgs/build-support/trivial-builders/test/default.nix | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/pkgs/build-support/trivial-builders/test/default.nix b/pkgs/build-support/trivial-builders/test/default.nix
index cde2014b5adc..683f4b9fd04f 100644
--- a/pkgs/build-support/trivial-builders/test/default.nix
+++ b/pkgs/build-support/trivial-builders/test/default.nix
@@ -11,7 +11,7 @@
 
 */
 
-{ callPackage, lib }:
+{ callPackage, lib, stdenv }:
 let
   inherit (lib) recurseIntoAttrs;
 in
@@ -19,7 +19,11 @@ recurseIntoAttrs {
   concat = callPackage ./concat-test.nix {};
   linkFarm = callPackage ./link-farm.nix {};
   overriding = callPackage ../test-overriding.nix {};
-  references = callPackage ./references.nix {};
+  references =
+    # VM test not supported beyond linux yet
+    if stdenv.hostPlatform.isLinux
+    then callPackage ./references.nix {}
+    else null;
   writeCBin = callPackage ./writeCBin.nix {};
   writeScriptBin = callPackage ./writeScriptBin.nix {};
   writeShellScript = callPackage ./write-shell-script.nix {};

From 0dd3989cef1fb458101ab6fd94221449401ec2af Mon Sep 17 00:00:00 2001
From: Robert Hensing <robert@roberthensing.nl>
Date: Wed, 26 Jul 2023 18:45:54 +0200
Subject: [PATCH 4/4] tests.trivial-builders.writeTextFile: Test
 meta.mainProgram logic

---
 .../trivial-builders/test/write-text-file.nix | 91 +++++++++++++------
 1 file changed, 64 insertions(+), 27 deletions(-)

diff --git a/pkgs/build-support/trivial-builders/test/write-text-file.nix b/pkgs/build-support/trivial-builders/test/write-text-file.nix
index ac83a75fca4a..2e6685c1980b 100644
--- a/pkgs/build-support/trivial-builders/test/write-text-file.nix
+++ b/pkgs/build-support/trivial-builders/test/write-text-file.nix
@@ -1,34 +1,71 @@
-{ writeTextFile }:
+/*
+  To run:
+
+      cd nixpkgs
+      nix-build -A tests.trivial-builders.writeTextFile
+
+  or to run an individual test case
+
+      cd nixpkgs
+      nix-build -A tests.trivial-builders.writeTextFile.foo
+*/
+{ lib, runCommand, runtimeShell, writeTextFile }:
 let
   veryWeirdName = ''here's a name with some "bad" characters, like spaces and quotes'';
-in writeTextFile {
-  name = "weird-names";
-  destination = "/etc/${veryWeirdName}";
-  text = ''passed!'';
-  checkPhase = ''
-    # intentionally hardcode everything here, to make sure
-    # Nix does not mess with file paths
+in
+lib.recurseIntoAttrs {
 
-    name="here's a name with some \"bad\" characters, like spaces and quotes"
-    fullPath="$out/etc/$name"
+  different-exe-name =
+    let
+      pkg = writeTextFile {
+        name = "bar";
+        destination = "/bin/foo";
+        executable = true;
+        text = ''
+          #!${runtimeShell}
+          echo hi
+        '';
+      };
+    in
+      assert pkg.meta.mainProgram == "foo";
+      assert baseNameOf (lib.getExe pkg) == "foo";
+      assert pkg.name == "bar";
+      runCommand "test-writeTextFile-different-exe-name" {} ''
+        PATH="${lib.makeBinPath [ pkg ]}:$PATH"
+        x=$(foo)
+        [[ "$x" == hi ]]
+        touch $out
+      '';
 
-    if [ -f "$fullPath" ]; then
-      echo "[PASS] File exists!"
-    else
-      echo "[FAIL] File was not created at expected path!"
-      exit 1
-    fi
+  weird-name = writeTextFile {
+    name = "weird-names";
+    destination = "/etc/${veryWeirdName}";
+    text = ''passed!'';
+    checkPhase = ''
+      # intentionally hardcode everything here, to make sure
+      # Nix does not mess with file paths
 
-    content=$(<"$fullPath")
-    expected="passed!"
+      name="here's a name with some \"bad\" characters, like spaces and quotes"
+      fullPath="$out/etc/$name"
 
-    if [ "$content" = "$expected" ]; then
-      echo "[PASS] Contents match!"
-    else
-      echo "[FAIL] File contents don't match!"
-      echo "       Expected: $expected"
-      echo "       Got:      $content"
-      exit 2
-    fi
-  '';
+      if [ -f "$fullPath" ]; then
+        echo "[PASS] File exists!"
+      else
+        echo "[FAIL] File was not created at expected path!"
+        exit 1
+      fi
+
+      content=$(<"$fullPath")
+      expected="passed!"
+
+      if [ "$content" = "$expected" ]; then
+        echo "[PASS] Contents match!"
+      else
+        echo "[FAIL] File contents don't match!"
+        echo "       Expected: $expected"
+        echo "       Got:      $content"
+        exit 2
+      fi
+    '';
+  };
 }