dev: Add Strutil::eval_as_bool (AcademySoftwareFoundation#4250)

Signed-off-by: Larry Gritz <lg@larrygritz.com>
lgritz · May 18, 2024 · 530987c · 530987c
1 parent 6fc6f83
commit 530987c
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Showing 4 changed files with 89 additions and 2 deletions.
diff --git a/src/include/OpenImageIO/strutil.h b/src/include/OpenImageIO/strutil.h
@@ -1155,6 +1155,19 @@ OIIO_UTIL_API size_t
 edit_distance(string_view a, string_view b,
               EditDistMetric metric = EditDistMetric::Levenshtein);
 
+
+/// Evaluate a string as a boolean value using the following heuristic:
+///   - If the string is a valid numeric value (represents an integer or
+///     floating point value), return true if it's non-zero, false if it's
+///     zero.
+///   - If the string is one of "false", "no", or "off", or if it contains
+///     only whitespace, return false.
+///   - All other non-empty strings return true.
+/// The comparisons are case-insensitive and ignore leading and trailing
+/// whitespace.
+OIIO_UTIL_API bool
+eval_as_bool(string_view value);
+
 }  // namespace Strutil
 
 

diff --git a/src/libutil/strutil.cpp b/src/libutil/strutil.cpp
@@ -1861,4 +1861,30 @@ Strutil::edit_distance(string_view a, string_view b, EditDistMetric metric)
     return levenshtein_distance(a, b);
 }
 
+
+
+/// Interpret a string as a boolean value using the following heuristic:
+///   - If the string is a valid numeric value (represents an integer or
+///     floating point value), return true if it's non-zero, false if it's
+///     zero.
+///   - If the string is one of "false", "no", or "off", or if it contains
+///     only whitespace, return false.
+///   - All other non-empty strings return true.
+/// The comparisons are case-insensitive and ignore leading and trailing
+/// whitespace.
+bool
+Strutil::eval_as_bool(string_view value)
+{
+    Strutil::trim_whitespace(value);
+    if (Strutil::string_is_int(value)) {
+        return Strutil::stoi(value) != 0;
+    } else if (Strutil::string_is_float(value)) {
+        return Strutil::stof(value) != 0.0f;
+    } else {
+        return !(value.empty() || Strutil::iequals(value, "false")
+                 || Strutil::iequals(value, "no")
+                 || Strutil::iequals(value, "off"));
+    }
+}
+
 OIIO_NAMESPACE_END
diff --git a/src/libutil/strutil_test.cpp b/src/libutil/strutil_test.cpp
@@ -1673,6 +1673,53 @@ test_base64_encode()
 
 
 
+void
+test_eval_as_bool()
+{
+    using namespace Strutil;
+    print("testing eval_as_bool()\n");
+
+    // Test cases for integer values
+    OIIO_CHECK_EQUAL(eval_as_bool("0"), false);
+    OIIO_CHECK_EQUAL(eval_as_bool("1"), true);
+    OIIO_CHECK_EQUAL(eval_as_bool("-1"), true);
+    OIIO_CHECK_EQUAL(eval_as_bool("10"), true);
+    OIIO_CHECK_EQUAL(eval_as_bool("-10"), true);
+
+    // Test cases for floating-point values
+    OIIO_CHECK_EQUAL(eval_as_bool("0.0"), false);
+    OIIO_CHECK_EQUAL(eval_as_bool("1.0"), true);
+    OIIO_CHECK_EQUAL(eval_as_bool("-1.0"), true);
+    OIIO_CHECK_EQUAL(eval_as_bool("10.5"), true);
+    OIIO_CHECK_EQUAL(eval_as_bool("-10.5"), true);
+
+    // Test cases for string values
+    OIIO_CHECK_EQUAL(eval_as_bool(""), false);
+    OIIO_CHECK_EQUAL(eval_as_bool("false"), false);
+    OIIO_CHECK_EQUAL(eval_as_bool("FALSE"), false);
+    OIIO_CHECK_EQUAL(eval_as_bool("no"), false);
+    OIIO_CHECK_EQUAL(eval_as_bool("NO"), false);
+    OIIO_CHECK_EQUAL(eval_as_bool("off"), false);
+    OIIO_CHECK_EQUAL(eval_as_bool("OFF"), false);
+
+    OIIO_CHECK_EQUAL(eval_as_bool("true"), true);
+    OIIO_CHECK_EQUAL(eval_as_bool("TRUE"), true);
+    OIIO_CHECK_EQUAL(eval_as_bool("yes"), true);
+    OIIO_CHECK_EQUAL(eval_as_bool("YES"), true);
+    OIIO_CHECK_EQUAL(eval_as_bool("on"), true);
+    OIIO_CHECK_EQUAL(eval_as_bool("ON"), true);
+    OIIO_CHECK_EQUAL(eval_as_bool("OpenImageIO"), true);
+
+    // Test whitespace, case insensitivity, other tricky cases
+    OIIO_CHECK_EQUAL(eval_as_bool("   "), false);
+    OIIO_CHECK_EQUAL(eval_as_bool("\t \n"), false);
+    OIIO_CHECK_EQUAL(eval_as_bool(" faLsE"), false);
+    OIIO_CHECK_EQUAL(eval_as_bool("\tOFf"), false);
+    OIIO_CHECK_EQUAL(eval_as_bool("off OpenImageIO"), true);
+}
+
+
+
 int
 main(int /*argc*/, char* /*argv*/[])
 {
@@ -1708,6 +1755,7 @@ main(int /*argc*/, char* /*argv*/[])
     test_datetime();
     test_edit_distance();
     test_base64_encode();
+    test_eval_as_bool();
 
     Strutil::debug("debug message\n");
 

diff --git a/src/oiiotool/oiiotool.cpp b/src/oiiotool/oiiotool.cpp
@@ -1121,7 +1121,7 @@ control_if(Oiiotool& ot, cspan<const char*> argv)
     if (ot.running()) {
         // string_view command = ot.express(argv[0]);
         string_view value = ot.express(argv[1]);
-        cond              = eval_as_bool(value);
+        cond              = Strutil::eval_as_bool(value);
         // Strutil::print("while: val='{}' cond={}\n", value, cond);
     } else {
         // If not running in the outer scope, don't even evaluate the
@@ -1184,7 +1184,7 @@ control_while(Oiiotool& ot, cspan<const char*> argv)
     if (ot.running()) {
         // string_view command = ot.express(argv[0]);
         string_view value = ot.express(argv[1]);
-        cond              = eval_as_bool(value);
+        cond              = Strutil::eval_as_bool(value);
         // Strutil::print("while: val='{}' cond={}\n", value, cond);
     } else {
         // If not running in the outer scope, don't even evaluate the