util: Add GetPathArg default path argument

ryanofsky · ryanofsky · commit b00c0c2a73b3 · 2022-02-09T18:19:48.000-05:00
Lets GetPathArg method be used more places for path arguments that have
default values, like "-settings" and BITCOIN_SETTINGS_FILENAME in the
next comment.

Also:

- Fix negated argument handling. Return path{} not path{"0"} when path
  argument is negated.

- Add new tests for default and negated cases

- Move GetPathArg() method declaration next to GetArg() declarations.
  The two methods are close substitutes for each, so this should help
  keep them consistent and make them more discoverable.
diff --git a/src/test/getarg_tests.cpp b/src/test/getarg_tests.cpp
@@ -249,6 +249,14 @@ BOOST_AUTO_TEST_CASE(patharg)
 
     ResetArgs("-dir=user/.bitcoin/.//");
     BOOST_CHECK_EQUAL(m_local_args.GetPathArg("-dir"), relative_path);
+
+    // Check negated and default arguments
+    ResetArgs("-dir=override");
+    BOOST_CHECK_EQUAL(m_local_args.GetPathArg("-dir", "default"), fs::path{"override"});
+    ResetArgs("");
+    BOOST_CHECK_EQUAL(m_local_args.GetPathArg("-dir", "default"), fs::path{"default"});
+    ResetArgs("-nodir");
+    BOOST_CHECK_EQUAL(m_local_args.GetPathArg("-dir", "default"), fs::path{""});
 }
 
 BOOST_AUTO_TEST_CASE(doubledash)
diff --git a/src/util/system.cpp b/src/util/system.cpp
@@ -386,9 +386,12 @@ std::optional<unsigned int> ArgsManager::GetArgFlags(const std::string& name) co
     return std::nullopt;
 }
 
-fs::path ArgsManager::GetPathArg(std::string pathlike_arg) const
+fs::path ArgsManager::GetPathArg(const std::string& arg, const fs::path& default_value) const
 {
-    auto result = fs::PathFromString(GetArg(pathlike_arg, "")).lexically_normal();
+    if (IsArgNegated(arg)) return fs::path{};
+    std::string path_str = GetArg(arg, "");
+    if (path_str.empty()) return default_value;
+    fs::path result = fs::PathFromString(path_str).lexically_normal();
     // Remove trailing slash, if present.
     return result.has_filename() ? result : result.parent_path();
 }
diff --git a/src/util/system.h b/src/util/system.h
@@ -264,16 +264,6 @@ class ArgsManager
      */
     std::optional<const Command> GetCommand() const;
 
-    /**
-     * Get a normalized path from a specified pathlike argument
-     *
-     * It is guaranteed that the returned path has no trailing slashes.
-     *
-     * @param pathlike_arg Pathlike argument to get a path from (e.g., "-datadir", "-blocksdir" or "-walletdir")
-     * @return Normalized path which is get from a specified pathlike argument
-     */
-    fs::path GetPathArg(std::string pathlike_arg) const;
-
     /**
      * Get blocks directory path
      *
@@ -336,6 +326,16 @@ class ArgsManager
      */
     std::string GetArg(const std::string& strArg, const std::string& strDefault) const;
 
+    /**
+     * Return path argument or default value
+     *
+     * It is guaranteed that the returned path has no trailing slashes.
+     *
+     * @param arg Argument to get a path from (e.g., "-datadir", "-blocksdir" or "-walletdir")
+     * @return Lexically normalized path without trailing separators
+     */
+    fs::path GetPathArg(const std::string& arg, const fs::path& default_value={}) const;
+
     /**
      * Return integer argument or default value
      *

Original file line number	Diff line number	Diff line change
`@@ -386,9 +386,12 @@ std::optional<unsigned int> ArgsManager::GetArgFlags(const std::string& name) co`
`386`	`386`	`return std::nullopt;`
`387`	`387`	`}`
`388`	`388`
`389`		`-fs::path ArgsManager::GetPathArg(std::string pathlike_arg) const`
	`389`	`+fs::path ArgsManager::GetPathArg(const std::string& arg, const fs::path& default_value) const`
`390`	`390`	`{`
`391`		`- auto result = fs::PathFromString(GetArg(pathlike_arg, "")).lexically_normal();`
	`391`	`+ if (IsArgNegated(arg)) return fs::path{};`
	`392`	`+ std::string path_str = GetArg(arg, "");`
	`393`	`+ if (path_str.empty()) return default_value;`
	`394`	`+ fs::path result = fs::PathFromString(path_str).lexically_normal();`
`392`	`395`	`// Remove trailing slash, if present.`
`393`	`396`	`return result.has_filename() ? result : result.parent_path();`
`394`	`397`	`}`