feat: new mfv_getcaslib macro

Fetches a caslib from a regular SAS libref

tests/viyaonly/mfv_getcaslib.test.sas

@@ -0,0 +1,69 @@
+/**
+  @file
+  @brief Testing mfv_getcaslib macro function
+
+  <h4> SAS Macros </h4>
+  @li mfv_getcaslib.sas
+  @li mp_assert.sas
+  @li mp_assertscope.sas
+
+**/
+
+options mprint;
+
+/* ------------------------------------------------------------------------ */
+/* Setup: start a CAS session and assign caslibs                            */
+/* ------------------------------------------------------------------------ */
+cas mysess;
+caslib _all_ assign;
+
+%let testcaslib=Public;
+
+libname castest cas caslib=&testcaslib;
+
+/* ------------------------------------------------------------------------ */
+%put TEST 1 - returns the caslib name for a valid CAS libref;
+/* ------------------------------------------------------------------------ */
+%mp_assert(
+  iftrue=(%mfv_getcaslib(castest)=%upcase(&testcaslib)),
+  desc=Check correct caslib name returned for a valid CAS libref
+)
+
+
+/* ------------------------------------------------------------------------ */
+%put TEST 2 - returns empty for a non-CAS libref (WORK);
+/* ------------------------------------------------------------------------ */
+%mp_assert(
+  iftrue=(%mfv_getcaslib(WORK)=),
+  desc=Check empty string returned for a non-CAS libref
+)
+
+
+/* ------------------------------------------------------------------------ */
+%put TEST 3 - returns empty for a libref that does not exist;
+/* ------------------------------------------------------------------------ */
+%mp_assert(
+  iftrue=(%mfv_getcaslib(DOESNOTEXIST)=),
+  desc=Check empty string returned for a non-existent libref
+)
+
+
+/* ------------------------------------------------------------------------ */
+%put TEST 5 - no scope leakage into global macro variables;
+/* ------------------------------------------------------------------------ */
+%mp_assertscope(SNAPSHOT)
+
+%let _rc=%mfv_getcaslib(castest);
+
+%mp_assertscope(COMPARE,
+  desc=Check mfv_getcaslib does not leak macro variables into GLOBAL scope,
+  ignorelist=_RC
+)
+
+
+/* ------------------------------------------------------------------------ */
+/* Teardown                                                                  */
+/* ------------------------------------------------------------------------ */
+cas mysess terminate;
+
+

viya/mfv_getcaslib.sas

@@ -0,0 +1,37 @@
+/**
+  @file mfv_getcaslib.sas
+  @brief Returns the CAS caslib name for a given SAS libref
+  @details Pure macro function.  Reads sashelp.vlibnam and returns
+    the sysvalue where sysname='Caslib' for the given libref.  This
+    is useful when the caslib name and libref name may differ.
+
+    Usage:
+
+        %put %mfv_getcaslib(lib=PUBLIC);
+
+  @param [in] lib SAS libref for which to return the CAS caslib name
+
+  @return Returns the CAS caslib name, or empty string if not found
+
+**/
+
+%macro mfv_getcaslib(lib);
+
+%local dsid rc result;
+
+%let dsid=%sysfunc(open(sashelp.vlibnam(
+  where=(libname="%upcase(&lib)" and sysname="Caslib")
+)));
+
+%if &dsid %then %do;
+  %let rc=%sysfunc(fetch(&dsid));
+  %if &rc=0 %then
+    %let result=%sysfunc(
+      getvarc(&dsid,%sysfunc(varnum(&dsid,SYSVALUE)))
+    );
+  %let rc=%sysfunc(close(&dsid));
+%end;
+
+&result
+
+%mend mfv_getcaslib;