Merge "cpp codegen redesign, unit test support"

tools/aconfig/src/codegen_cpp.rs

@@ -16,13 +16,18 @@
 
 use anyhow::{ensure, Result};
 use serde::Serialize;
+use std::path::PathBuf;
 use tinytemplate::TinyTemplate;
 
 use crate::codegen;
-use crate::commands::OutputFile;
+use crate::commands::{CodegenMode, OutputFile};
 use crate::protos::{ProtoFlagPermission, ProtoFlagState, ProtoParsedFlag};
 
-pub fn generate_cpp_code<'a, I>(package: &str, parsed_flags_iter: I) -> Result<OutputFile>
+pub fn generate_cpp_code<'a, I>(
+    package: &str,
+    parsed_flags_iter: I,
+    codegen_mode: CodegenMode,
+) -> Result<Vec<OutputFile>>
 where
     I: Iterator<Item = &'a ProtoParsedFlag>,
 {
@@ -37,29 +42,66 @@ where
         cpp_namespace,
         package: package.to_string(),
         readwrite,
+        for_prod: codegen_mode == CodegenMode::Production,
         class_elements,
     };
+
+    let files = [
+        FileSpec {
+            name: &format!("{}.h", header),
+            template: include_str!("../templates/cpp_exported_header.template"),
+            dir: "include",
+        },
+        FileSpec {
+            name: &format!("{}.cc", header),
+            template: include_str!("../templates/cpp_source_file.template"),
+            dir: "",
+        },
+        FileSpec {
+            name: &format!("{}_flag_provider.h", header),
+            template: match codegen_mode {
+                CodegenMode::Production => {
+                    include_str!("../templates/cpp_prod_flag_provider.template")
+                }
+                CodegenMode::Test => include_str!("../templates/cpp_test_flag_provider.template"),
+            },
+            dir: "",
+        },
+    ];
+    files.iter().map(|file| generate_file(file, &context)).collect()
+}
+
+pub fn generate_file(file: &FileSpec, context: &Context) -> Result<OutputFile> {
     let mut template = TinyTemplate::new();
-    template.add_template("cpp_code_gen", include_str!("../templates/cpp.template"))?;
-    let contents = template.render("cpp_code_gen", &context)?;
-    let path = ["aconfig", &(header + ".h")].iter().collect();
+    template.add_template(file.name, file.template)?;
+    let contents = template.render(file.name, &context)?;
+    let path: PathBuf = [&file.dir, &file.name].iter().collect();
     Ok(OutputFile { contents: contents.into(), path })
 }
 
 #[derive(Serialize)]
-struct Context {
+pub struct FileSpec<'a> {
+    pub name: &'a str,
+    pub template: &'a str,
+    pub dir: &'a str,
+}
+
+#[derive(Serialize)]
+pub struct Context {
     pub header: String,
     pub cpp_namespace: String,
     pub package: String,
     pub readwrite: bool,
+    pub for_prod: bool,
     pub class_elements: Vec<ClassElement>,
 }
 
 #[derive(Serialize)]
-struct ClassElement {
+pub struct ClassElement {
     pub readwrite: bool,
     pub default_value: String,
     pub flag_name: String,
+    pub uppercase_flag_name: String,
     pub device_config_namespace: String,
     pub device_config_flag: String,
 }
@@ -73,6 +115,7 @@ fn create_class_element(package: &str, pf: &ProtoParsedFlag) -> ClassElement {
             "false".to_string()
         },
         flag_name: pf.name().to_string(),
+        uppercase_flag_name: pf.name().to_string().to_ascii_uppercase(),
         device_config_namespace: pf.namespace().to_string(),
         device_config_flag: codegen::create_device_config_ident(package, pf.name())
             .expect("values checked at flag parse time"),
@@ -82,51 +125,325 @@ fn create_class_element(package: &str, pf: &ProtoParsedFlag) -> ClassElement {
 #[cfg(test)]
 mod tests {
     use super::*;
+    use std::collections::HashMap;
 
-    #[test]
-    fn test_generate_cpp_code() {
-        let parsed_flags = crate::test::parse_test_flags();
-        let generated =
-            generate_cpp_code(crate::test::TEST_PACKAGE, parsed_flags.parsed_flag.iter()).unwrap();
-        assert_eq!("aconfig/com_android_aconfig_test.h", format!("{}", generated.path.display()));
-        let expected = r#"
+    const EXPORTED_PROD_HEADER_EXPECTED: &str = r#"
 #ifndef com_android_aconfig_test_HEADER_H
 #define com_android_aconfig_test_HEADER_H
-#include <server_configurable_flags/get_flags.h>
 
+#include <string>
+#include <memory>
+#include <server_configurable_flags/get_flags.h>
 using namespace server_configurable_flags;
 
 namespace com::android::aconfig::test {
-    static const bool disabled_ro() {
+class flag_provider_interface {
+public:
+
+    virtual ~flag_provider_interface() = default;
+
+    virtual bool disabled_ro() = 0;
+
+    virtual bool disabled_rw() = 0;
+
+    virtual bool enabled_ro() = 0;
+
+    virtual bool enabled_rw() = 0;
+
+    virtual void override_flag(std::string const&, bool) {}
+
+    virtual void reset_overrides() {}
+};
+
+extern std::unique_ptr<flag_provider_interface> provider_;
+
+extern std::string const DISABLED_RO;
+extern std::string const DISABLED_RW;
+extern std::string const ENABLED_RO;
+extern std::string const ENABLED_RW;
+
+inline bool disabled_ro() {
+    return false;
+}
+
+inline bool disabled_rw() {
+    return provider_->disabled_rw();
+}
+
+inline bool enabled_ro() {
+    return true;
+}
+
+inline bool enabled_rw() {
+    return provider_->enabled_rw();
+}
+
+inline void override_flag(std::string const& name, bool val) {
+    return provider_->override_flag(name, val);
+}
+
+inline void reset_overrides() {
+    return provider_->reset_overrides();
+}
+
+}
+#endif
+"#;
+
+    const EXPORTED_TEST_HEADER_EXPECTED: &str = r#"
+#ifndef com_android_aconfig_test_HEADER_H
+#define com_android_aconfig_test_HEADER_H
+
+#include <string>
+#include <memory>
+#include <server_configurable_flags/get_flags.h>
+using namespace server_configurable_flags;
+
+namespace com::android::aconfig::test {
+class flag_provider_interface {
+public:
+
+    virtual ~flag_provider_interface() = default;
+
+    virtual bool disabled_ro() = 0;
+
+    virtual bool disabled_rw() = 0;
+
+    virtual bool enabled_ro() = 0;
+
+    virtual bool enabled_rw() = 0;
+
+    virtual void override_flag(std::string const&, bool) {}
+
+    virtual void reset_overrides() {}
+};
+
+extern std::unique_ptr<flag_provider_interface> provider_;
+
+extern std::string const DISABLED_RO;
+extern std::string const DISABLED_RW;
+extern std::string const ENABLED_RO;
+extern std::string const ENABLED_RW;
+
+inline bool disabled_ro() {
+    return provider_->disabled_ro();
+}
+
+inline bool disabled_rw() {
+    return provider_->disabled_rw();
+}
+
+inline bool enabled_ro() {
+    return provider_->enabled_ro();
+}
+
+inline bool enabled_rw() {
+    return provider_->enabled_rw();
+}
+
+inline void override_flag(std::string const& name, bool val) {
+    return provider_->override_flag(name, val);
+}
+
+inline void reset_overrides() {
+    return provider_->reset_overrides();
+}
+
+}
+#endif
+"#;
+
+    const PROD_FLAG_PROVIDER_HEADER_EXPECTED: &str = r#"
+#ifndef com_android_aconfig_test_flag_provider_HEADER_H
+#define com_android_aconfig_test_flag_provider_HEADER_H
+
+#include "com_android_aconfig_test.h"
+
+namespace com::android::aconfig::test {
+class flag_provider : public flag_provider_interface {
+public:
+
+    virtual bool disabled_ro() override {
         return false;
     }
 
-    static const bool disabled_rw() {
+    virtual bool disabled_rw() override {
         return GetServerConfigurableFlag(
             "aconfig_test",
             "com.android.aconfig.test.disabled_rw",
             "false") == "true";
     }
 
-    static const bool enabled_ro() {
+    virtual bool enabled_ro() override {
         return true;
     }
 
-    static const bool enabled_rw() {
+    virtual bool enabled_rw() override {
         return GetServerConfigurableFlag(
             "aconfig_test",
             "com.android.aconfig.test.enabled_rw",
             "true") == "true";
     }
+};
 }
 #endif
 "#;
+
+    const TEST_FLAG_PROVIDER_HEADER_EXPECTED: &str = r#"
+#ifndef com_android_aconfig_test_flag_provider_HEADER_H
+#define com_android_aconfig_test_flag_provider_HEADER_H
+
+#include "com_android_aconfig_test.h"
+
+#include <unordered_map>
+#include <unordered_set>
+#include <cassert>
+
+namespace com::android::aconfig::test {
+class flag_provider : public flag_provider_interface {
+private:
+    std::unordered_map<std::string, bool> overrides_;
+    std::unordered_set<std::string> flag_names_;
+
+public:
+
+    flag_provider()
+        : overrides_(),
+          flag_names_() {
+        flag_names_.insert(DISABLED_RO);
+        flag_names_.insert(DISABLED_RW);
+        flag_names_.insert(ENABLED_RO);
+        flag_names_.insert(ENABLED_RW);
+    }
+
+    virtual bool disabled_ro() override {
+        auto it = overrides_.find(DISABLED_RO);
+        if (it != overrides_.end()) {
+            return it->second;
+        } else {
+            return false;
+        }
+    }
+
+    virtual bool disabled_rw() override {
+        auto it = overrides_.find(DISABLED_RW);
+        if (it != overrides_.end()) {
+            return it->second;
+        } else {
+            return GetServerConfigurableFlag(
+                "aconfig_test",
+                "com.android.aconfig.test.disabled_rw",
+                "false") == "true";
+        }
+    }
+
+    virtual bool enabled_ro() override {
+        auto it = overrides_.find(ENABLED_RO);
+        if (it != overrides_.end()) {
+            return it->second;
+        } else {
+            return true;
+        }
+    }
+
+    virtual bool enabled_rw() override {
+        auto it = overrides_.find(ENABLED_RW);
+        if (it != overrides_.end()) {
+            return it->second;
+        } else {
+            return GetServerConfigurableFlag(
+                "aconfig_test",
+                "com.android.aconfig.test.enabled_rw",
+                "true") == "true";
+        }
+    }
+
+    virtual void override_flag(std::string const& flag, bool val) override {
+        assert(flag_names_.count(flag));
+        overrides_[flag] = val;
+    }
+
+    virtual void reset_overrides() override {
+        overrides_.clear();
+    }
+};
+}
+#endif
+"#;
+
+    const SOURCE_FILE_EXPECTED: &str = r#"
+#include "com_android_aconfig_test.h"
+#include "com_android_aconfig_test_flag_provider.h"
+
+namespace com::android::aconfig::test {
+
+    std::string const DISABLED_RO = "com.android.aconfig.test.disabled_ro";
+    std::string const DISABLED_RW = "com.android.aconfig.test.disabled_rw";
+    std::string const ENABLED_RO = "com.android.aconfig.test.enabled_ro";
+    std::string const ENABLED_RW = "com.android.aconfig.test.enabled_rw";
+
+    std::unique_ptr<flag_provider_interface> provider_ =
+        std::make_unique<flag_provider>();
+}
+"#;
+
+    fn test_generate_cpp_code(mode: CodegenMode) {
+        let parsed_flags = crate::test::parse_test_flags();
+        let generated =
+            generate_cpp_code(crate::test::TEST_PACKAGE, parsed_flags.parsed_flag.iter(), mode)
+                .unwrap();
+        let mut generated_files_map = HashMap::new();
+        for file in generated {
+            generated_files_map.insert(
+                String::from(file.path.to_str().unwrap()),
+                String::from_utf8(file.contents.clone()).unwrap(),
+            );
+        }
+
+        let mut target_file_path = String::from("include/com_android_aconfig_test.h");
+        assert!(generated_files_map.contains_key(&target_file_path));
         assert_eq!(
             None,
             crate::test::first_significant_code_diff(
-                expected,
-                &String::from_utf8(generated.contents).unwrap()
+                match mode {
+                    CodegenMode::Production => EXPORTED_PROD_HEADER_EXPECTED,
+                    CodegenMode::Test => EXPORTED_TEST_HEADER_EXPECTED,
+                },
+                generated_files_map.get(&target_file_path).unwrap()
+            )
+        );
+
+        target_file_path = String::from("com_android_aconfig_test_flag_provider.h");
+        assert!(generated_files_map.contains_key(&target_file_path));
+        assert_eq!(
+            None,
+            crate::test::first_significant_code_diff(
+                match mode {
+                    CodegenMode::Production => PROD_FLAG_PROVIDER_HEADER_EXPECTED,
+                    CodegenMode::Test => TEST_FLAG_PROVIDER_HEADER_EXPECTED,
+                },
+                generated_files_map.get(&target_file_path).unwrap()
+            )
+        );
+
+        target_file_path = String::from("com_android_aconfig_test.cc");
+        assert!(generated_files_map.contains_key(&target_file_path));
+        assert_eq!(
+            None,
+            crate::test::first_significant_code_diff(
+                SOURCE_FILE_EXPECTED,
+                generated_files_map.get(&target_file_path).unwrap()
             )
         );
     }
+
+    #[test]
+    fn test_generate_cpp_code_for_prod() {
+        test_generate_cpp_code(CodegenMode::Production);
+    }
+
+    #[test]
+    fn test_generate_cpp_code_for_test() {
+        test_generate_cpp_code(CodegenMode::Test);
+    }
 }

tools/aconfig/src/commands.rs

@@ -143,12 +143,12 @@ pub fn create_java_lib(mut input: Input, codegen_mode: CodegenMode) -> Result<Ve
     generate_java_code(package, parsed_flags.parsed_flag.iter(), codegen_mode)
 }
 
-pub fn create_cpp_lib(mut input: Input) -> Result<OutputFile> {
+pub fn create_cpp_lib(mut input: Input, codegen_mode: CodegenMode) -> Result<Vec<OutputFile>> {
     let parsed_flags = input.try_parse_flags()?;
     let Some(package) = find_unique_package(&parsed_flags) else {
         bail!("no parsed flags, or the parsed flags use different packages");
     };
-    generate_cpp_code(package, parsed_flags.parsed_flag.iter())
+    generate_cpp_code(package, parsed_flags.parsed_flag.iter(), codegen_mode)
 }
 
 pub fn create_rust_lib(mut input: Input) -> Result<OutputFile> {

tools/aconfig/src/main.rs

@@ -60,7 +60,13 @@ fn cli() -> Command {
         .subcommand(
             Command::new("create-cpp-lib")
                 .arg(Arg::new("cache").long("cache").required(true))
-                .arg(Arg::new("out").long("out").required(true)),
+                .arg(Arg::new("out").long("out").required(true))
+                .arg(
+                    Arg::new("mode")
+                        .long("mode")
+                        .value_parser(EnumValueParser::<commands::CodegenMode>::new())
+                        .default_value("production"),
+                ),
         )
         .subcommand(
             Command::new("create-rust-lib")
@@ -163,9 +169,12 @@ fn main() -> Result<()> {
         }
         Some(("create-cpp-lib", sub_matches)) => {
             let cache = open_single_file(sub_matches, "cache")?;
-            let generated_file = commands::create_cpp_lib(cache)?;
+            let mode = get_required_arg::<CodegenMode>(sub_matches, "mode")?;
+            let generated_files = commands::create_cpp_lib(cache, *mode)?;
             let dir = PathBuf::from(get_required_arg::<String>(sub_matches, "out")?);
-            write_output_file_realtive_to_dir(&dir, &generated_file)?;
+            generated_files
+                .iter()
+                .try_for_each(|file| write_output_file_realtive_to_dir(&dir, file))?;
         }
         Some(("create-rust-lib", sub_matches)) => {
             let cache = open_single_file(sub_matches, "cache")?;

tools/aconfig/templates/cpp_exported_header.template

@@ -0,0 +1,48 @@
+#ifndef {header}_HEADER_H
+#define {header}_HEADER_H
+
+#include <string>
+#include <memory>
+{{ if readwrite }}
+#include <server_configurable_flags/get_flags.h>
+using namespace server_configurable_flags;
+{{ endif }}
+namespace {cpp_namespace} \{
+
+class flag_provider_interface \{
+public:
+    virtual ~flag_provider_interface() = default;
+    {{ for item in class_elements}}
+    virtual bool {item.flag_name}() = 0;
+    {{ endfor }}
+    virtual void override_flag(std::string const&, bool) \{}
+
+    virtual void reset_overrides() \{}
+};
+
+extern std::unique_ptr<flag_provider_interface> provider_;
+{{ for item in class_elements}}
+extern std::string const {item.uppercase_flag_name};{{ endfor }}
+{{ for item in class_elements}}
+inline bool {item.flag_name}() \{
+    {{ if for_prod }}
+    {{ if not item.readwrite- }}
+    return {item.default_value};
+    {{ -else- }}
+    return provider_->{item.flag_name}();
+    {{ -endif }}
+    {{ -else- }}
+    return provider_->{item.flag_name}();
+    {{ -endif }}
+}
+{{ endfor }}
+inline void override_flag(std::string const& name, bool val) \{
+    return provider_->override_flag(name, val);
+}
+
+inline void reset_overrides() \{
+    return provider_->reset_overrides();
+}
+
+}
+#endif

tools/aconfig/templates/cpp_prod_flag_provider.template

@@ -1,12 +1,12 @@
-#ifndef {header}_HEADER_H
-#define {header}_HEADER_H
-{{ if readwrite }}
-#include <server_configurable_flags/get_flags.h>
-using namespace server_configurable_flags;
-{{ endif }}
+#ifndef {header}_flag_provider_HEADER_H
+#define {header}_flag_provider_HEADER_H
+#include "{header}.h"
+
 namespace {cpp_namespace} \{
+class flag_provider : public flag_provider_interface \{
+public:
     {{ for item in class_elements}}
-    static const bool {item.flag_name}() \{
+    virtual bool {item.flag_name}() override \{
         {{ if item.readwrite- }}
         return GetServerConfigurableFlag(
             "{item.device_config_namespace}",
@@ -17,5 +17,6 @@ namespace {cpp_namespace} \{
         {{ -endif }}
     }
     {{ endfor }}
+};
 }
 #endif

tools/aconfig/templates/cpp_source_file.template

@@ -0,0 +1,10 @@
+
+#include "{header}.h"
+#include "{header}_flag_provider.h"
+
+namespace {cpp_namespace} \{
+{{ for item in class_elements}}
+std::string const {item.uppercase_flag_name} = "{item.device_config_flag}";{{ endfor }}
+std::unique_ptr<flag_provider_interface> provider_ =
+    std::make_unique<flag_provider>();
+}

tools/aconfig/templates/cpp_test_flag_provider.template

@@ -0,0 +1,49 @@
+#ifndef {header}_flag_provider_HEADER_H
+#define {header}_flag_provider_HEADER_H
+#include "{header}.h"
+
+#include <unordered_map>
+#include <unordered_set>
+#include <cassert>
+
+namespace {cpp_namespace} \{
+class flag_provider : public flag_provider_interface \{
+private:
+    std::unordered_map<std::string, bool> overrides_;
+    std::unordered_set<std::string> flag_names_;
+
+public:
+    flag_provider()
+        : overrides_(),
+        flag_names_() \{
+        {{ for item in class_elements}}
+        flag_names_.insert({item.uppercase_flag_name});{{ endfor }}
+    }
+    {{ for item in class_elements}}
+    virtual bool {item.flag_name}() override \{
+        auto it = overrides_.find({item.uppercase_flag_name});
+	      if (it != overrides_.end()) \{
+	          return it->second;
+        } else \{
+          {{ if item.readwrite- }}
+          return GetServerConfigurableFlag(
+              "{item.device_config_namespace}",
+              "{item.device_config_flag}",
+              "{item.default_value}") == "true";
+          {{ -else- }}
+              return {item.default_value};
+          {{ -endif }}
+        }
+    }
+    {{ endfor }}
+    virtual void override_flag(std::string const& flag, bool val) override \{
+        assert(flag_names_.count(flag));
+        overrides_[flag] = val;
+    }
+
+    virtual void reset_overrides() override \{
+        overrides_.clear();
+    }
+};
+}
+#endif