feat(nix): indentation queries

tests/indent/nix/general.nix

@@ -0,0 +1,130 @@
+{ lib }:
+with lib.lists;
+with lib.types;
+with lib.attrsets;
+with lib.strings;
+with (import ./inspect.nix { inherit lib; }).predicates;
+
+let
+  inherit (lib.options) mergeOneOption;
+
+  setTypes = type:
+    mapAttrs (name: value:
+      assert type.check value;
+      setType type.name ({ inherit name; } // value));
+
+in rec {
+
+  ################################################################################
+
+  types.openSignificantByte = mkOptionType {
+    name = "significant-byte";
+    description = "Endianness";
+    merge = mergeOneOption;
+  };
+
+  types.significantByte = enum (attrValues significantBytes);
+
+  significantBytes = setTypes types.openSignificantByte {
+    bigEndian = { };
+    littleEndian = { };
+  };
+
+  ################################################################################
+
+  # Reasonable power of 2
+  types.bitWidth = enum [ 8 16 32 64 128 ];
+
+  ################################################################################
+
+  types.openCpuType = mkOptionType {
+    name = "cpu-type";
+    description = "instruction set architecture name and information";
+    merge = mergeOneOption;
+    check = x:
+      types.bitWidth.check x.bits && (if 8 < x.bits then
+        types.significantByte.check x.significantByte
+      else
+        !(x ? significantByte));
+  };
+
+  types.cpuType = enum (attrValues cpuTypes);
+
+  cpuTypes = with significantBytes;
+    setTypes types.openCpuType {
+      arm = {
+        bits = 32;
+        significantByte = littleEndian;
+        family = "arm";
+      };
+      armv5tel = {
+        bits = 32;
+        significantByte = littleEndian;
+        family = "arm";
+        version = "5";
+        arch = "armv5t";
+      };
+    };
+
+  isCompatible = a: b:
+    with cpuTypes;
+    lib.any lib.id [
+      # x86
+      (b == i386 && isCompatible a i486)
+      (b == i486 && isCompatible a i586)
+      (b == i586 && isCompatible a i686)
+
+      # ARMv6
+      (b == armv6l && isCompatible a armv6m)
+      (b == armv6m && isCompatible a armv7l)
+    ];
+
+  ################################################################################
+
+  types.openVendor = mkOptionType {
+    name = "vendor";
+    description = "vendor for the platform";
+    merge = mergeOneOption;
+  };
+
+  abis = setTypes types.openAbi {
+    cygnus = { };
+    msvc = { };
+
+    # Other architectures should use ELF in embedded situations.
+    elf = { };
+
+    androideabi = { };
+    android = {
+      assertions = [{
+        assertion = platform: !platform.isAarch32;
+        message = ''
+          The "android" ABI is not for 32-bit ARM. Use "androideabi" instead.
+        '';
+      }];
+    };
+  };
+
+  ################################################################################
+
+  types.parsedPlatform = mkOptionType {
+    name = "system";
+    description =
+      "fully parsed representation of llvm- or nix-style platform tuple";
+    merge = mergeOneOption;
+    check = { cpu, vendor, kernel, abi, }:
+      types.cpuType.check cpu && types.vendor.check vendor
+      && types.kernel.check kernel && types.abi.check abi;
+  };
+
+  isSystem = isType "system";
+
+  mkSystem = components:
+    assert types.parsedPlatform.check components;
+    setType "system" components;
+
+  mkSystemFromString = s:
+    mkSystemFromSkeleton (mkSkeletonFromList (lib.splitString "-" s));
+
+  ################################################################################
+}