Add error reporting to machine spec paser

Currently machine specification (`/etc/nix/machine`) parser fails
with a vague exception if the file had incorrect format.
This commit adds verbose exceptions and unit-tests for the parser.

1 files changed, 169 insertions, 0 deletions

diff --git a/src/libstore/tests/machines.cc b/src/libstore/tests/machines.cc
new file mode 100644
index 000000000..f51052b14
--- /dev/null
+++ b/src/libstore/tests/machines.cc
@@ -0,0 +1,169 @@
+#include "machines.hh"
+#include "globals.hh"
+
+#include <gmock/gmock-matchers.h>
+
+using testing::Contains;
+using testing::ElementsAre;
+using testing::EndsWith;
+using testing::Eq;
+using testing::Field;
+using testing::SizeIs;
+
+using nix::absPath;
+using nix::FormatError;
+using nix::getMachines;
+using nix::Machine;
+using nix::Machines;
+using nix::pathExists;
+using nix::Settings;
+using nix::settings;
+
+class Environment : public ::testing::Environment {
+  public:
+    void SetUp() override { settings.thisSystem = "TEST_ARCH-TEST_OS"; }
+};
+
+testing::Environment* const foo_env =
+    testing::AddGlobalTestEnvironment(new Environment);
+
+TEST(machines, getMachinesWithEmptyBuilders) {
+    settings.builders = "";
+    Machines actual = getMachines();
+    ASSERT_THAT(actual, SizeIs(0));
+}
+
+TEST(machines, getMachinesUriOnly) {
+    settings.builders = "nix@scratchy.labs.cs.uu.nl";
+    Machines actual = getMachines();
+    ASSERT_THAT(actual, SizeIs(1));
+    EXPECT_THAT(actual[0], Field(&Machine::storeUri, Eq("ssh://nix@scratchy.labs.cs.uu.nl")));
+    EXPECT_THAT(actual[0], Field(&Machine::systemTypes, ElementsAre("TEST_ARCH-TEST_OS")));
+    EXPECT_THAT(actual[0], Field(&Machine::sshKey, SizeIs(0)));
+    EXPECT_THAT(actual[0], Field(&Machine::maxJobs, Eq(1)));
+    EXPECT_THAT(actual[0], Field(&Machine::speedFactor, Eq(1)));
+    EXPECT_THAT(actual[0], Field(&Machine::supportedFeatures, SizeIs(0)));
+    EXPECT_THAT(actual[0], Field(&Machine::mandatoryFeatures, SizeIs(0)));
+    EXPECT_THAT(actual[0], Field(&Machine::sshPublicHostKey, SizeIs(0)));
+}
+
+TEST(machines, getMachinesDefaults) {
+    settings.builders = "nix@scratchy.labs.cs.uu.nl - - - - - - -";
+    Machines actual = getMachines();
+    ASSERT_THAT(actual, SizeIs(1));
+    EXPECT_THAT(actual[0], Field(&Machine::storeUri, Eq("ssh://nix@scratchy.labs.cs.uu.nl")));
+    EXPECT_THAT(actual[0], Field(&Machine::systemTypes, ElementsAre("TEST_ARCH-TEST_OS")));
+    EXPECT_THAT(actual[0], Field(&Machine::sshKey, SizeIs(0)));
+    EXPECT_THAT(actual[0], Field(&Machine::maxJobs, Eq(1)));
+    EXPECT_THAT(actual[0], Field(&Machine::speedFactor, Eq(1)));
+    EXPECT_THAT(actual[0], Field(&Machine::supportedFeatures, SizeIs(0)));
+    EXPECT_THAT(actual[0], Field(&Machine::mandatoryFeatures, SizeIs(0)));
+    EXPECT_THAT(actual[0], Field(&Machine::sshPublicHostKey, SizeIs(0)));
+}
+
+TEST(machines, getMachinesWithNewLineSeparator) {
+    settings.builders = "nix@scratchy.labs.cs.uu.nl\nnix@itchy.labs.cs.uu.nl";
+    Machines actual = getMachines();
+    ASSERT_THAT(actual, SizeIs(2));
+    EXPECT_THAT(actual, Contains(Field(&Machine::storeUri, EndsWith("nix@scratchy.labs.cs.uu.nl"))));
+    EXPECT_THAT(actual, Contains(Field(&Machine::storeUri, EndsWith("nix@itchy.labs.cs.uu.nl"))));
+}
+
+TEST(machines, getMachinesWithSemicolonSeparator) {
+    settings.builders = "nix@scratchy.labs.cs.uu.nl ; nix@itchy.labs.cs.uu.nl";
+    Machines actual = getMachines();
+    EXPECT_THAT(actual, SizeIs(2));
+    EXPECT_THAT(actual, Contains(Field(&Machine::storeUri, EndsWith("nix@scratchy.labs.cs.uu.nl"))));
+    EXPECT_THAT(actual, Contains(Field(&Machine::storeUri, EndsWith("nix@itchy.labs.cs.uu.nl"))));
+}
+
+TEST(machines, getMachinesWithCorrectCompleteSingleBuilder) {
+    settings.builders = "nix@scratchy.labs.cs.uu.nl     i686-linux      "
+                        "/home/nix/.ssh/id_scratchy_auto        8 3 kvm "
+                        "benchmark SSH+HOST+PUBLIC+KEY+BASE64+ENCODED==";
+    Machines actual = getMachines();
+    ASSERT_THAT(actual, SizeIs(1));
+    EXPECT_THAT(actual[0], Field(&Machine::storeUri, EndsWith("nix@scratchy.labs.cs.uu.nl")));
+    EXPECT_THAT(actual[0], Field(&Machine::systemTypes, ElementsAre("i686-linux")));
+    EXPECT_THAT(actual[0], Field(&Machine::sshKey, Eq("/home/nix/.ssh/id_scratchy_auto")));
+    EXPECT_THAT(actual[0], Field(&Machine::maxJobs, Eq(8)));
+    EXPECT_THAT(actual[0], Field(&Machine::speedFactor, Eq(3)));
+    EXPECT_THAT(actual[0], Field(&Machine::supportedFeatures, ElementsAre("kvm")));
+    EXPECT_THAT(actual[0], Field(&Machine::mandatoryFeatures, ElementsAre("benchmark")));
+    EXPECT_THAT(actual[0], Field(&Machine::sshPublicHostKey, Eq("SSH+HOST+PUBLIC+KEY+BASE64+ENCODED==")));
+}
+
+TEST(machines,
+     getMachinesWithCorrectCompleteSingleBuilderWithTabColumnDelimiter) {
+    settings.builders =
+        "nix@scratchy.labs.cs.uu.nl\ti686-linux\t/home/nix/.ssh/"
+        "id_scratchy_auto\t8\t3\tkvm\tbenchmark\tSSH+HOST+PUBLIC+"
+        "KEY+BASE64+ENCODED==";
+    Machines actual = getMachines();
+    ASSERT_THAT(actual, SizeIs(1));
+    EXPECT_THAT(actual[0], Field(&Machine::storeUri, EndsWith("nix@scratchy.labs.cs.uu.nl")));
+    EXPECT_THAT(actual[0], Field(&Machine::systemTypes, ElementsAre("i686-linux")));
+    EXPECT_THAT(actual[0], Field(&Machine::sshKey, Eq("/home/nix/.ssh/id_scratchy_auto")));
+    EXPECT_THAT(actual[0], Field(&Machine::maxJobs, Eq(8)));
+    EXPECT_THAT(actual[0], Field(&Machine::speedFactor, Eq(3)));
+    EXPECT_THAT(actual[0], Field(&Machine::supportedFeatures, ElementsAre("kvm")));
+    EXPECT_THAT(actual[0], Field(&Machine::mandatoryFeatures, ElementsAre("benchmark")));
+    EXPECT_THAT(actual[0], Field(&Machine::sshPublicHostKey, Eq("SSH+HOST+PUBLIC+KEY+BASE64+ENCODED==")));
+}
+
+TEST(machines, getMachinesWithMultiOptions) {
+    settings.builders = "nix@scratchy.labs.cs.uu.nl Arch1,Arch2 - - - "
+                        "SupportedFeature1,SupportedFeature2 "
+                        "MandatoryFeature1,MandatoryFeature2";
+    Machines actual = getMachines();
+    ASSERT_THAT(actual, SizeIs(1));
+    EXPECT_THAT(actual[0], Field(&Machine::storeUri, EndsWith("nix@scratchy.labs.cs.uu.nl")));
+    EXPECT_THAT(actual[0], Field(&Machine::systemTypes, ElementsAre("Arch1", "Arch2")));
+    EXPECT_THAT(actual[0], Field(&Machine::supportedFeatures, ElementsAre("SupportedFeature1", "SupportedFeature2")));
+    EXPECT_THAT(actual[0], Field(&Machine::mandatoryFeatures, ElementsAre("MandatoryFeature1", "MandatoryFeature2")));
+}
+
+TEST(machines, getMachinesWithIncorrectFormat) {
+    settings.builders = "nix@scratchy.labs.cs.uu.nl - - eight";
+    EXPECT_THROW(getMachines(), FormatError);
+    settings.builders = "nix@scratchy.labs.cs.uu.nl - - -1";
+    EXPECT_THROW(getMachines(), FormatError);
+    settings.builders = "nix@scratchy.labs.cs.uu.nl - - 8 three";
+    EXPECT_THROW(getMachines(), FormatError);
+    settings.builders = "nix@scratchy.labs.cs.uu.nl - - 8 -3";
+    EXPECT_THROW(getMachines(), FormatError);
+    settings.builders = "nix@scratchy.labs.cs.uu.nl - - 8 3 - - BAD_BASE64";
+    EXPECT_THROW(getMachines(), FormatError);
+}
+
+TEST(machines, getMachinesWithCorrectFileReference) {
+    auto path = absPath("src/libstore/tests/test-data/machines.valid");
+    ASSERT_TRUE(pathExists(path));
+
+    settings.builders = std::string("@") + path;
+    Machines actual = getMachines();
+    ASSERT_THAT(actual, SizeIs(3));
+    EXPECT_THAT(actual, Contains(Field(&Machine::storeUri, EndsWith("nix@scratchy.labs.cs.uu.nl"))));
+    EXPECT_THAT(actual, Contains(Field(&Machine::storeUri, EndsWith("nix@itchy.labs.cs.uu.nl"))));
+    EXPECT_THAT(actual, Contains(Field(&Machine::storeUri, EndsWith("nix@poochie.labs.cs.uu.nl"))));
+}
+
+TEST(machines, getMachinesWithCorrectFileReferenceToEmptyFile) {
+    auto path = "/dev/null";
+    ASSERT_TRUE(pathExists(path));
+
+    settings.builders = std::string("@") + path;
+    Machines actual = getMachines();
+    ASSERT_THAT(actual, SizeIs(0));
+}
+
+TEST(machines, getMachinesWithIncorrectFileReference) {
+    settings.builders = std::string("@") + absPath("/not/a/file");
+    Machines actual = getMachines();
+    ASSERT_THAT(actual, SizeIs(0));
+}
+
+TEST(machines, getMachinesWithCorrectFileReferenceToIncorrectFile) {
+    settings.builders = std::string("@") + absPath("src/libstore/tests/test-data/machines.bad_format");
+    EXPECT_THROW(getMachines(), FormatError);
+}