new utility function "utils::expand_type" to convert type labels to numeric strings

doc/src/Developer_utils.rst

@@ -211,6 +211,9 @@ Argument processing
 .. doxygenfunction:: expand_args
    :project: progguide
 
+.. doxygenfunction:: expand_type
+   :project: progguide
+
 Convenience functions
 ^^^^^^^^^^^^^^^^^^^^^
 

src/utils.cpp

@@ -20,6 +20,7 @@
 #include "fix.h"
 #include "fmt/chrono.h"
 #include "input.h"
+#include "label_map.h"
 #include "memory.h"
 #include "modify.h"
 #include "text_file_reader.h"
@@ -766,6 +767,26 @@ int utils::expand_args(const char *file, int line, int narg, char **arg, int mod
   return newarg;
 }
 
+/* -------------------------------------------------------------------------
+   Expand type string to numeric string from labelmap.
+   Return copy of expanded type or null pointer.
+------------------------------------------------------------------------- */
+
+char *utils::expand_type(const char *file, int line, const std::string &str, int mode, LAMMPS *lmp)
+{
+  if (!lmp) return nullptr;
+  if (is_type(str) == 1) {
+    if (!lmp->atom->labelmapflag)
+      lmp->error->all(file, line, "Type string {} cannot be used without a labelmap", str);
+
+    int type = lmp->atom->lmap->find(str, mode);
+    if (type == -1) lmp->error->all(file, line, "Type string {} not found in labelmap", str);
+
+    return utils::strdup(std::to_string(type));
+  } else
+    return nullptr;
+}
+
 /* ----------------------------------------------------------------------
    Make copy of string in new storage. Works like the (non-portable)
    C-style strdup() but also accepts a C++ string as argument.

src/utils.h

@@ -359,6 +359,24 @@ namespace utils {
   int expand_args(const char *file, int line, int narg, char **arg, int mode, char **&earg,
                   LAMMPS *lmp);
 
+  /*! Expand type label string into its equivalent numeric type
+   *
+   *  This function checks if a given string may be a type label and
+   *  then searches the labelmap type indicated by the *mode* argument
+   *  for the corresponding numeric type.  If this is found a copy of
+   *  the numeric type string is made and returned. Otherwise a null
+   *  pointer is returned.
+   *  If a string is returned, the calling code must free it with delete[].
+   *
+   * \param file  name of source file for error message
+   * \param line  line number in source file for error message
+   * \param str   type string to be expanded
+   * \param mode  select labelmap using constants from Atom class
+   * \param lmp   pointer to top-level LAMMPS class instance
+   * \return      pointer to expanded string or null pointer */
+
+  char *expand_type(const char *file, int line, const std::string &str, int mode, LAMMPS *lmp);
+
   /*! Make C-style copy of string in new storage
    *
    * This allocates a storage buffer and copies the C-style or

unittest/commands/test_labelmap.cpp

@@ -63,6 +63,13 @@ TEST_F(LabelMapTest, Atoms)
     BEGIN_HIDE_OUTPUT();
     command("region box block 0 2 0 2 0 2");
     command("create_box 4 box");
+    END_HIDE_OUTPUT();
+    EXPECT_EQ(domain->box_exist, 1);
+    EXPECT_EQ(atom->lmap, nullptr);
+    TEST_FAILURE(".*ERROR: Type string C1 cannot be used without a labelmap.*",
+                 utils::expand_type(FLERR, "C1", Atom::ATOM, lmp););
+
+    BEGIN_HIDE_OUTPUT();
     command("labelmap atom 2 N1");
     command("labelmap atom 3 O1 4 H1");
     command("mass * 1.0");
@@ -89,6 +96,22 @@ TEST_F(LabelMapTest, Atoms)
     EXPECT_EQ(atom->lmap->find("X", Atom::ATOM), -1);
     EXPECT_DOUBLE_EQ(atom->mass[3], 10.0);
 
+    EXPECT_EQ(utils::expand_type(FLERR, "1", Atom::ATOM, lmp), nullptr);
+    EXPECT_EQ(utils::expand_type(FLERR, "*3", Atom::ATOM, lmp), nullptr);
+    EXPECT_EQ(utils::expand_type(FLERR, "1*2", Atom::ATOM, lmp), nullptr);
+    EXPECT_EQ(utils::expand_type(FLERR, "*", Atom::ATOM, lmp), nullptr);
+    EXPECT_EQ(utils::expand_type(FLERR, "**", Atom::ATOM, lmp), nullptr);
+    EXPECT_EQ(utils::expand_type(FLERR, "1*2*", Atom::ATOM, lmp), nullptr);
+
+    auto expanded = utils::expand_type(FLERR, "C1", Atom::ATOM, lmp);
+    EXPECT_THAT(expanded, StrEq("1"));
+    delete[] expanded;
+    expanded = utils::expand_type(FLERR, "O#", Atom::ATOM, lmp);
+    EXPECT_THAT(expanded, StrEq("3"));
+    delete[] expanded;
+    TEST_FAILURE(".*ERROR: Type string XX not found in labelmap.*",
+                 utils::expand_type(FLERR, "XX", Atom::ATOM, lmp););
+
     TEST_FAILURE(".*ERROR: Labelmap atom type 0 must be within 1-4.*",
                  command("labelmap atom 0 C1"););
     TEST_FAILURE(".*ERROR: Labelmap atom type 5 must be within 1-4.*",
@@ -238,6 +261,24 @@ TEST_F(LabelMapTest, Topology)
     EXPECT_EQ(atom->lmap->find("X", Atom::ATOM), -1);
     EXPECT_EQ(atom->lmap->find("N2'-C1\"-N2'", Atom::BOND), -1);
     platform::unlink("labelmap_topology.inc");
+
+    auto expanded = utils::expand_type(FLERR, "N2'", Atom::ATOM, lmp);
+    EXPECT_THAT(expanded, StrEq("2"));
+    delete[] expanded;
+    expanded = utils::expand_type(FLERR, "[C1][C1]", Atom::BOND, lmp);
+    EXPECT_THAT(expanded, StrEq("2"));
+    delete[] expanded;
+    expanded = utils::expand_type(FLERR, "C1-N2-C1", Atom::ANGLE, lmp);
+    EXPECT_THAT(expanded, StrEq("1"));
+    delete[] expanded;
+    expanded = utils::expand_type(FLERR, "C1-N2-C1-N2", Atom::DIHEDRAL, lmp);
+    EXPECT_THAT(expanded, StrEq("1"));
+    delete[] expanded;
+    expanded = utils::expand_type(FLERR, "C1-N2-C1-N2", Atom::IMPROPER, lmp);
+    EXPECT_THAT(expanded, StrEq("1"));
+    delete[] expanded;
+    TEST_FAILURE(".*ERROR: Type string XX not found in labelmap.*",
+                 utils::expand_type(FLERR, "XX", Atom::BOND, lmp););
 }
 } // namespace LAMMPS_NS
 

unittest/commands/test_variables.cpp

@@ -33,10 +33,10 @@
 bool verbose = false;
 
 namespace LAMMPS_NS {
+using MathConst::MY_PI;
 using ::testing::ContainsRegex;
 using ::testing::ExitedWithCode;
 using ::testing::StrEq;
-using MathConst::MY_PI;
 
 class VariableTest : public LAMMPSTest {
 protected:
@@ -196,8 +196,10 @@ TEST_F(VariableTest, CreateDelete)
 
     TEST_FAILURE(".*ERROR: Illegal variable command.*", command("variable"););
     TEST_FAILURE(".*ERROR: Illegal variable index command.*", command("variable dummy index"););
-    TEST_FAILURE(".*ERROR: Illegal variable delete command: expected 2 arguments but found 3.*", command("variable dummy delete xxx"););
+    TEST_FAILURE(".*ERROR: Illegal variable delete command: expected 2 arguments but found 3.*",
-    TEST_FAILURE(".*ERROR: Invalid variable loop argument: -1.*", command("variable dummy loop -1"););
+                 command("variable dummy delete xxx"););
+    TEST_FAILURE(".*ERROR: Invalid variable loop argument: -1.*",
+                 command("variable dummy loop -1"););
     TEST_FAILURE(".*ERROR: Illegal variable loop command.*", command("variable dummy loop 10 1"););
     TEST_FAILURE(".*ERROR: Unknown variable keyword: xxx.*", command("variable dummy xxxx"););
     TEST_FAILURE(".*ERROR: Cannot redefine variable as a different style.*",
@@ -402,8 +404,9 @@ TEST_F(VariableTest, Functions)
                  command("print \"$(extract_setting()\""););
     TEST_FAILURE(".*ERROR: Invalid extract_setting.. function syntax in variable formula.*",
                  command("print \"$(extract_setting(one,two))\""););
-    TEST_FAILURE(".*ERROR: Unknown setting nprocs for extract_setting.. function in variable formula.*",
+    TEST_FAILURE(
-                 command("print \"$(extract_setting(nprocs))\""););
+        ".*ERROR: Unknown setting nprocs for extract_setting.. function in variable formula.*",
+        command("print \"$(extract_setting(nprocs))\""););
 }
 
 TEST_F(VariableTest, IfCommand)