From 3c769fa242d507aa9f2b05a2946247cd175ddd64 Mon Sep 17 00:00:00 2001
From: Martchus <martchus@gmx.net>
Date: Sun, 26 Jun 2022 11:20:24 +0200
Subject: [PATCH] Add greedy-flag for argument parser

This is useful if one needs to pass subsequent arguments as-is to another
nested argument parser.
---
 application/argumentparser.cpp |  5 +++--
 application/argumentparser.h   |  1 +
 tests/argumentparsertests.cpp  | 21 +++++++++++++++++++++
 3 files changed, 25 insertions(+), 2 deletions(-)

diff --git a/application/argumentparser.cpp b/application/argumentparser.cpp
index aecbfe9..fde521c 100644
--- a/application/argumentparser.cpp
+++ b/application/argumentparser.cpp
@@ -206,7 +206,8 @@ bool ArgumentReader::read(ArgumentVector &args)
     // iterate through all argument denotations; loop might exit earlier when an denotation is unknown
     while (argv != end) {
         // check whether there are still values to read
-        if (values && lastArgInLevel->requiredValueCount() != Argument::varValueCount && values->size() < lastArgInLevel->requiredValueCount()) {
+        if (values && ((lastArgInLevel->requiredValueCount() != Argument::varValueCount) || (lastArgInLevel->flags() & Argument::Flags::Greedy))
+            && values->size() < lastArgInLevel->requiredValueCount()) {
             // read arg as value and continue with next arg
             values->emplace_back(argDenotation ? argDenotation : *argv);
             ++index;
@@ -1092,7 +1093,7 @@ void ArgumentParser::verifyArgs(const ArgumentVector &args)
         assert(!arg->abbreviation() || find(abbreviations.cbegin(), abbreviations.cend(), arg->abbreviation()) == abbreviations.cend());
         abbreviations.push_back(arg->abbreviation());
         assert(!arg->name() || find_if(names.cbegin(), names.cend(), [arg](const char *name) { return !strcmp(arg->name(), name); }) == names.cend());
-        assert(arg->requiredValueCount() == 0 || arg->subArguments().size() == 0);
+        assert(arg->requiredValueCount() == 0 || arg->subArguments().size() == 0 || (arg->flags() & Argument::Flags::Greedy));
         names.emplace_back(arg->name());
     }
     for (const Argument *arg : args) {
diff --git a/application/argumentparser.h b/application/argumentparser.h
index b85576d..c012ef9 100644
--- a/application/argumentparser.h
+++ b/application/argumentparser.h
@@ -273,6 +273,7 @@ public:
         Implicit = 0x2,
         Operation = 0x4,
         Deprecated = 0x8,
+        Greedy = 0x10,
     };
 
     Argument(const char *name, char abbreviation = '\0', const char *description = nullptr, const char *example = nullptr);
diff --git a/tests/argumentparsertests.cpp b/tests/argumentparsertests.cpp
index 26f0575..e6b9937 100644
--- a/tests/argumentparsertests.cpp
+++ b/tests/argumentparsertests.cpp
@@ -452,6 +452,27 @@ void ArgumentParserTests::testParsing()
     CPPUNIT_ASSERT(fieldsArg.isPresent());
     CPPUNIT_ASSERT_EQUAL("fields"sv, std::string_view(fieldsArg.values().at(0)));
     CPPUNIT_ASSERT_EQUAL("album=test"sv, std::string_view(fieldsArg.values().at(1)));
+
+    // greedy-flag
+    const char *argv19[] = { "tageditor", "get", "--fields", "foo", "bar", "--help" };
+    parser.resetArgs();
+    try {
+        parser.parseArgs(6, argv19, ParseArgumentBehavior::CheckConstraints | ParseArgumentBehavior::InvokeCallbacks);
+        CPPUNIT_FAIL("Exception expected.");
+    } catch (const ParseError &e) {
+        CPPUNIT_ASSERT_EQUAL_MESSAGE("--help assumed to be an argument without greedy-flag (leading to error)",
+            "The argument \"help\" can not be combined with \"get\"."sv, std::string_view(e.what()));
+    }
+    parser.resetArgs();
+    fieldsArg.setFlags(Argument::Flags::Greedy, true);
+    parser.parseArgs(6, argv19, ParseArgumentBehavior::CheckConstraints | ParseArgumentBehavior::InvokeCallbacks);
+    CPPUNIT_ASSERT(displayTagInfoArg.isPresent());
+    CPPUNIT_ASSERT(fieldsArg.isPresent());
+    CPPUNIT_ASSERT_MESSAGE("--help not considered an argument with greedy-flag", !parser.helpArg().isPresent());
+    CPPUNIT_ASSERT_EQUAL("foo"sv, std::string_view(fieldsArg.values().at(0)));
+    CPPUNIT_ASSERT_EQUAL("bar"sv, std::string_view(fieldsArg.values().at(1)));
+    CPPUNIT_ASSERT_EQUAL("--help"sv, std::string_view(fieldsArg.values().at(2)));
+    CPPUNIT_ASSERT_THROW(fieldsArg.values().at(3), std::out_of_range);
 }
 
 /*!