summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
Diffstat
-rw-r--r--Help/command/cmake_parse_arguments.rst6
-rw-r--r--Help/manual/cmake-policies.7.rst1
-rw-r--r--Help/policy/CMP0174.rst33
-rw-r--r--Source/cmParseArgumentsCommand.cxx32
-rw-r--r--Source/cmPolicies.h6
-rw-r--r--Tests/RunCMake/cmake_parse_arguments/CornerCasesArgvN-stderr.txt11
-rw-r--r--Tests/RunCMake/cmake_parse_arguments/CornerCasesArgvN.cmake45
-rw-r--r--Tests/RunCMake/cmake_parse_arguments/test_utils.cmake4
8 files changed, 131 insertions, 7 deletions
diff --git a/Help/command/cmake_parse_arguments.rst b/Help/command/cmake_parse_arguments.rst
index 0bb1d91..70dbeeb 100644
--- a/Help/command/cmake_parse_arguments.rst
+++ b/Help/command/cmake_parse_arguments.rst
@@ -70,6 +70,12 @@ whether your macro was called with unrecognized parameters.
received values. This can be checked to see if there were keywords without
any values given.
+.. versionchanged:: 3.31
+ If a ``<one_value_keyword>`` is followed by an empty string as its value,
+ policy :policy:`CMP0174` controls whether a corresponding
+ ``<prefix>_<keyword>`` variable is defined or not.
+
+
Consider the following example macro, ``my_install()``, which takes similar
arguments to the real :command:`install` command:
diff --git a/Help/manual/cmake-policies.7.rst b/Help/manual/cmake-policies.7.rst
index 4130e14..e257c36 100644
--- a/Help/manual/cmake-policies.7.rst
+++ b/Help/manual/cmake-policies.7.rst
@@ -57,6 +57,7 @@ Policies Introduced by CMake 3.31
.. toctree::
:maxdepth: 1
+ CMP0174: cmake_parse_arguments(PARSE_ARGV) defines a variable for an empty string after a single-value keyword. </policy/CMP0174>
CMP0173: The CMakeFindFrameworks module is removed. </policy/CMP0173>
CMP0172: The CPack module enables per-machine installation by default in the CPack WIX Generator. </policy/CMP0172>
CMP0171: 'codegen' is a reserved target name. </policy/CMP0171>
diff --git a/Help/policy/CMP0174.rst b/Help/policy/CMP0174.rst
new file mode 100644
index 0000000..bde0a03
--- /dev/null
+++ b/Help/policy/CMP0174.rst
@@ -0,0 +1,33 @@
+CMP0174
+-------
+
+.. versionadded:: 3.31
+
+:command:`cmake_parse_arguments(PARSE_ARGV)` defines a variable for an empty
+string after a single-value keyword.
+
+One of the main reasons for using the ``PARSE_ARGV`` form of the
+:command:`cmake_parse_arguments` command is to more robustly handle corner
+cases related to empty values. The non-``PARSE_ARGV`` form doesn't preserve
+empty arguments, but the ``PARSE_ARGV`` form does. For each single-value
+keyword given, a variable should be defined if the keyword is followed by a
+value. Prior to CMake 3.31, no variable would be defined if the value given
+was an empty string. This meant the code could not detect the difference
+between the keyword not being given, and it being given but with an empty
+value, except by iterating over all the arguments and checking if the keyword
+is present.
+
+For the ``OLD`` behavior of this policy,
+:command:`cmake_parse_arguments(PARSE_ARGV)` does not define a variable for a
+single-value keyword followed by an empty string.
+For the ``NEW`` behavior, :command:`cmake_parse_arguments(PARSE_ARGV)` always
+defines a variable for each keyword given in the arguments, even a single-value
+keyword with an empty string as its value. With the ``NEW`` behavior, the
+code can robustly check if a single-value keyword was given with any value
+using just ``if(DEFINED <prefix>_<keyword>)``.
+
+.. |INTRODUCED_IN_CMAKE_VERSION| replace:: 3.31
+.. |WARNS_OR_DOES_NOT_WARN| replace:: warns
+.. include:: STANDARD_ADVICE.txt
+
+.. include:: DEPRECATED.txt
diff --git a/Source/cmParseArgumentsCommand.cxx b/Source/cmParseArgumentsCommand.cxx
index 9b1e76b..f6e7937 100644
--- a/Source/cmParseArgumentsCommand.cxx
+++ b/Source/cmParseArgumentsCommand.cxx
@@ -6,6 +6,7 @@
#include <set>
#include <utility>
+#include <cm/optional>
#include <cm/string_view>
#include "cmArgumentParser.h"
@@ -14,6 +15,7 @@
#include "cmList.h"
#include "cmMakefile.h"
#include "cmMessageType.h"
+#include "cmPolicies.h"
#include "cmRange.h"
#include "cmStringAlgorithms.h"
#include "cmSystemTools.h"
@@ -41,7 +43,7 @@ std::string JoinList(std::vector<std::string> const& arg, bool escape)
}
using options_map = std::map<std::string, bool>;
-using single_map = std::map<std::string, std::string>;
+using single_map = std::map<std::string, cm::optional<std::string>>;
using multi_map =
std::map<std::string, ArgumentParser::NonEmpty<std::vector<std::string>>>;
using options_set = std::set<cm::string_view>;
@@ -82,12 +84,32 @@ static void PassParsedArguments(
iter.second ? "TRUE" : "FALSE");
}
+ const cmPolicies::PolicyStatus cmp0174 =
+ makefile.GetPolicyStatus(cmPolicies::CMP0174);
for (auto const& iter : singleValArgs) {
- if (!iter.second.empty()) {
- makefile.AddDefinition(cmStrCat(prefix, iter.first), iter.second);
- } else {
- makefile.RemoveDefinition(prefix + iter.first);
+ if (iter.second.has_value()) {
+ // So far, we only know that the keyword was given, not whether a value
+ // was provided after the keyword
+ if (keywordsMissingValues.find(iter.first) ==
+ keywordsMissingValues.end()) {
+ // A (possibly empty) value was given
+ if (cmp0174 == cmPolicies::NEW || !iter.second->empty()) {
+ makefile.AddDefinition(cmStrCat(prefix, iter.first), *iter.second);
+ continue;
+ }
+ if (cmp0174 == cmPolicies::WARN) {
+ makefile.IssueMessage(
+ MessageType::AUTHOR_WARNING,
+ cmStrCat("An empty string was given as the value after the ",
+ iter.first,
+ " keyword. Policy CMP0174 is not set, so "
+ "cmake_parse_arguments() will unset the ",
+ prefix, iter.first,
+ " variable rather than setting it to an empty string."));
+ }
+ }
}
+ makefile.RemoveDefinition(prefix + iter.first);
}
for (auto const& iter : multiValArgs) {
diff --git a/Source/cmPolicies.h b/Source/cmPolicies.h
index 2c3763f..7b056ae 100644
--- a/Source/cmPolicies.h
+++ b/Source/cmPolicies.h
@@ -533,7 +533,11 @@ class cmMakefile;
"the CPack WIX Generator.", \
3, 31, 0, cmPolicies::WARN) \
SELECT(POLICY, CMP0173, "The CMakeFindFrameworks module is removed.", 3, \
- 31, 0, cmPolicies::WARN)
+ 31, 0, cmPolicies::WARN) \
+ SELECT(POLICY, CMP0174, \
+ "cmake_parse_arguments(PARSE_ARGV) defines a variable for an empty " \
+ "string after a single-value keyword.", \
+ 3, 31, 0, cmPolicies::WARN)
#define CM_SELECT_ID(F, A1, A2, A3, A4, A5, A6) F(A1)
#define CM_FOR_EACH_POLICY_ID(POLICY) \
diff --git a/Tests/RunCMake/cmake_parse_arguments/CornerCasesArgvN-stderr.txt b/Tests/RunCMake/cmake_parse_arguments/CornerCasesArgvN-stderr.txt
new file mode 100644
index 0000000..1b87306
--- /dev/null
+++ b/Tests/RunCMake/cmake_parse_arguments/CornerCasesArgvN-stderr.txt
@@ -0,0 +1,11 @@
+Testing CMP0174 = NEW
+Testing CMP0174 = OLD
+Testing CMP0174 = WARN
+CMake Warning \(dev\) at CornerCasesArgvN\.cmake:[0-9]+ \(cmake_parse_arguments\):
+ An empty string was given as the value after the P1 keyword\. Policy
+ CMP0174 is not set, so cmake_parse_arguments\(\) will unset the arg_P1
+ variable rather than setting it to an empty string\.
+Call Stack \(most recent call first\):
+ CornerCasesArgvN\.cmake:[0-9]+ \(test_cmp0174_warn\)
+ CMakeLists\.txt:[0-9]+ \(include\)
+This warning is for project developers\. Use -Wno-dev to suppress it\.
diff --git a/Tests/RunCMake/cmake_parse_arguments/CornerCasesArgvN.cmake b/Tests/RunCMake/cmake_parse_arguments/CornerCasesArgvN.cmake
index 807ed03..04c0219 100644
--- a/Tests/RunCMake/cmake_parse_arguments/CornerCasesArgvN.cmake
+++ b/Tests/RunCMake/cmake_parse_arguments/CornerCasesArgvN.cmake
@@ -51,3 +51,48 @@ function(test4)
TEST(upref_UNPARSED_ARGUMENTS foo "bar;none")
endfunction()
test4(MULTI foo bar\\ none)
+
+# Single-value keyword with empty string as value
+message(NOTICE "Testing CMP0174 = NEW")
+block(SCOPE_FOR POLICIES)
+ cmake_policy(SET CMP0174 NEW)
+ function(test_cmp0174_new_missing)
+ cmake_parse_arguments(PARSE_ARGV 0 arg "" "P1;P2" "")
+ TEST(arg_KEYWORDS_MISSING_VALUES "P2")
+ TEST(arg_P1 "")
+ TEST(arg_P2 "UNDEFINED")
+ endfunction()
+ test_cmp0174_new_missing(P1 "" P2)
+
+ function(test_cmp0174_new_no_missing)
+ cmake_parse_arguments(PARSE_ARGV 0 arg "" "P1;P2" "")
+ TEST(arg_KEYWORDS_MISSING_VALUES "UNDEFINED")
+ TEST(arg_P1 "")
+ TEST(arg_P2 "UNDEFINED")
+ endfunction()
+ test_cmp0174_new_no_missing(P1 "")
+endblock()
+
+message(NOTICE "Testing CMP0174 = OLD")
+block(SCOPE_FOR POLICIES)
+ cmake_policy(SET CMP0174 OLD)
+ function(test_cmp0174_old)
+ cmake_parse_arguments(PARSE_ARGV 0 arg "" "P1;P2" "")
+ TEST(arg_KEYWORDS_MISSING_VALUES "P2")
+ TEST(arg_P1 "UNDEFINED")
+ TEST(arg_P2 "UNDEFINED")
+ endfunction()
+ test_cmp0174_old(P1 "" P2)
+endblock()
+
+message(NOTICE "Testing CMP0174 = WARN")
+block(SCOPE_FOR POLICIES)
+ cmake_policy(VERSION 3.30) # WARN
+ function(test_cmp0174_warn)
+ cmake_parse_arguments(PARSE_ARGV 0 arg "" "P1;P2" "")
+ TEST(arg_KEYWORDS_MISSING_VALUES "P2")
+ TEST(arg_P1 "UNDEFINED")
+ TEST(arg_P2 "UNDEFINED")
+ endfunction()
+ test_cmp0174_warn(P1 "" P2)
+endblock()
diff --git a/Tests/RunCMake/cmake_parse_arguments/test_utils.cmake b/Tests/RunCMake/cmake_parse_arguments/test_utils.cmake
index 9ce99b8..23b804e 100644
--- a/Tests/RunCMake/cmake_parse_arguments/test_utils.cmake
+++ b/Tests/RunCMake/cmake_parse_arguments/test_utils.cmake
@@ -13,6 +13,8 @@ function(TEST variable)
if(DEFINED ${variable})
message(FATAL_ERROR "'${variable}' shall be undefined but has value '${${variable}}'")
endif()
+ elseif(NOT DEFINED ${variable})
+ message(FATAL_ERROR "'${variable}' should be defined but is not")
elseif("${expected}" STREQUAL "FALSE")
if(NOT ${variable} STREQUAL "FALSE")
message(FATAL_ERROR "'${variable}' shall be FALSE")
@@ -23,7 +25,7 @@ function(TEST variable)
endif()
else()
if(NOT ${variable} STREQUAL "${expected}")
- message(FATAL_ERROR "'${variable}' shall be '${expected}'")
+ message(FATAL_ERROR "'${variable}' shall be '${expected}' but has value '${${variable}}'")
endif()
endif()
endif()
generated by cgit v0.12 at 2025-09-12 17:30:17 (GMT)