FHIRPath changes for as - case and singleton issues

org.hl7.fhir.r4/src/main/java/org/hl7/fhir/r4/utils/FHIRPathEngine.java

@@ -61,6 +61,7 @@ import org.hl7.fhir.utilities.MergedList;
 import org.hl7.fhir.utilities.MergedList.MergeNode;
 import org.hl7.fhir.utilities.SourceLocation;
 import org.hl7.fhir.utilities.Utilities;
+import org.hl7.fhir.utilities.VersionUtilities;
 import org.hl7.fhir.utilities.i18n.I18nConstants;
 import org.hl7.fhir.utilities.validation.ValidationOptions;
 import org.hl7.fhir.utilities.xhtml.NodeType;
@@ -260,6 +261,8 @@ public class FHIRPathEngine {
   private boolean allowPolymorphicNames;
   private boolean doImplicitStringConversion;
   private boolean liquidMode; // in liquid mode, || terminates the expression and hands the parser back to the host
+  private boolean doNotEnforceAsSingletonRule;
+  private boolean doNotEnforceAsCaseSensitive;
 
   // if the fhir path expressions are allowed to use constants beyond those defined in the specification
   // the application can implement them by providing a constant resolver 
@@ -369,8 +372,15 @@ public class FHIRPathEngine {
         primitiveTypes.add(sd.getName());
       }
     }
+    initFlags();
   }
 
+  private void initFlags() {
+    if (!VersionUtilities.isR5VerOrLater(worker.getVersion())) {
+      doNotEnforceAsCaseSensitive = true;
+      doNotEnforceAsSingletonRule = true;
+    }
+  }
 
   // --- 3 methods to override in children -------------------------------------------------------
   // if you don't override, it falls through to the using the base reference implementation 
@@ -453,6 +463,22 @@ public class FHIRPathEngine {
     this.doImplicitStringConversion = doImplicitStringConversion;
   }
 
+  public boolean isDoNotEnforceAsSingletonRule() {
+    return doNotEnforceAsSingletonRule;
+  }
+
+  public void setDoNotEnforceAsSingletonRule(boolean doNotEnforceAsSingletonRule) {
+    this.doNotEnforceAsSingletonRule = doNotEnforceAsSingletonRule;
+  }
+
+  public boolean isDoNotEnforceAsCaseSensitive() {
+    return doNotEnforceAsCaseSensitive;
+  }
+
+  public void setDoNotEnforceAsCaseSensitive(boolean doNotEnforceAsCaseSensitive) {
+    this.doNotEnforceAsCaseSensitive = doNotEnforceAsCaseSensitive;
+  }
+
   // --- public API -------------------------------------------------------
   /**
    * Parse a path for later use using execute
@@ -1789,11 +1815,11 @@ public class FHIRPathEngine {
       if (!isKnownType(tn)) {
         throw new PathEngineException("The type "+tn+" is not valid");
       }
-      if (left.size() > 1) {
+      if (!doNotEnforceAsSingletonRule && left.size() > 1) {
-        throw new PathEngineException("Attempt to use as on more than one item ("+left.size()+")");
+        throw new PathEngineException("Attempt to use as on more than one item ("+left.size()+", '"+expr.toString()+"')");
       }
       for (Base nextLeft : left) {
-        if (tn.equals(nextLeft.fhirType())) {
+        if (compareTypeNames(tn, nextLeft.fhirType())) {
           result.add(nextLeft);
         }
       }
@@ -1801,9 +1827,19 @@ public class FHIRPathEngine {
     return result;
   }
 
+  private boolean compareTypeNames(String left, String right) {
+    if (doNotEnforceAsCaseSensitive) {
+      return left.equalsIgnoreCase(right);            
+    } else {
+      return left.equals(right);      
+    }
+  }
 
   private boolean isKnownType(String tn) {
     if (!tn.contains(".")) {
+      if (Utilities.existsInList(tn, "String", "Boolean", "Integer", "Decimal", "Quantity", "DateTime", "Time", "SimpleTypeInfo", "ClassInfo")) {
+        return true;
+      }
       try {
         return worker.fetchTypeDefinition(tn) != null;
       } catch (Exception e) {
@@ -4584,7 +4620,7 @@ public class FHIRPathEngine {
     if (!isKnownType(tn)) {
       throw new PathEngineException("The type "+tn+" is not valid");
     }
-    if (focus.size() > 1) {
+    if (!doNotEnforceAsSingletonRule && focus.size() > 1) {
       throw new PathEngineException("Attempt to use as() on more than one item ("+focus.size()+")");
     }
     
@@ -4603,7 +4639,7 @@ public class FHIRPathEngine {
         } else {
           StructureDefinition sd = worker.fetchTypeDefinition(b.fhirType());
           while (sd != null) {
-            if (tnp.equals(sd.getType())) {
+            if (compareTypeNames(tnp, sd.getType())) {
               result.add(b);
               break;
             }

org.hl7.fhir.r4/src/test/java/org/hl7/fhir/r4/test/FHIRPathTests.java

@@ -201,6 +201,9 @@ public class FHIRPathTests {
       }
     }
     
+    fp.setDoNotEnforceAsCaseSensitive(false);
+    fp.setDoNotEnforceAsSingletonRule(false);
+    
     if (node != null) {
       try {
         outcome = fp.evaluate(res, node);

org.hl7.fhir.r4b/src/main/java/org/hl7/fhir/r4b/utils/FHIRPathEngine.java

@@ -62,6 +62,7 @@ import org.hl7.fhir.utilities.MergedList;
 import org.hl7.fhir.utilities.MergedList.MergeNode;
 import org.hl7.fhir.utilities.SourceLocation;
 import org.hl7.fhir.utilities.Utilities;
+import org.hl7.fhir.utilities.VersionUtilities;
 import org.hl7.fhir.utilities.i18n.I18nConstants;
 import org.hl7.fhir.utilities.validation.ValidationOptions;
 import org.hl7.fhir.utilities.xhtml.NodeType;
@@ -257,6 +258,8 @@ public class FHIRPathEngine {
   private boolean allowPolymorphicNames;
   private boolean doImplicitStringConversion;
   private boolean liquidMode; // in liquid mode, || terminates the expression and hands the parser back to the host
+  private boolean doNotEnforceAsSingletonRule;
+  private boolean doNotEnforceAsCaseSensitive;
 
   // if the fhir path expressions are allowed to use constants beyond those defined in the specification
   // the application can implement them by providing a constant resolver 
@@ -366,8 +369,15 @@ public class FHIRPathEngine {
         primitiveTypes.add(sd.getName());
       }
     }
+    initFlags();
   }
 
+  private void initFlags() {
+    if (!VersionUtilities.isR5VerOrLater(worker.getVersion())) {
+      doNotEnforceAsCaseSensitive = true;
+      doNotEnforceAsSingletonRule = true;
+    }
+  }
 
   // --- 3 methods to override in children -------------------------------------------------------
   // if you don't override, it falls through to the using the base reference implementation 
@@ -450,6 +460,22 @@ public class FHIRPathEngine {
     this.doImplicitStringConversion = doImplicitStringConversion;
   }
 
+  public boolean isDoNotEnforceAsSingletonRule() {
+    return doNotEnforceAsSingletonRule;
+  }
+
+  public void setDoNotEnforceAsSingletonRule(boolean doNotEnforceAsSingletonRule) {
+    this.doNotEnforceAsSingletonRule = doNotEnforceAsSingletonRule;
+  }
+
+  public boolean isDoNotEnforceAsCaseSensitive() {
+    return doNotEnforceAsCaseSensitive;
+  }
+
+  public void setDoNotEnforceAsCaseSensitive(boolean doNotEnforceAsCaseSensitive) {
+    this.doNotEnforceAsCaseSensitive = doNotEnforceAsCaseSensitive;
+  }
+
   // --- public API -------------------------------------------------------
   /**
    * Parse a path for later use using execute
@@ -1785,11 +1811,11 @@ public class FHIRPathEngine {
       if (!isKnownType(tn)) {
         throw new PathEngineException("The type "+tn+" is not valid");
       }
-      if (left.size() > 1) {
+      if (!doNotEnforceAsSingletonRule && left.size() > 1) {
-        throw new PathEngineException("Attempt to use as on more than one item ("+left.size()+")");
+        throw new PathEngineException("Attempt to use as on more than one item ("+left.size()+", '"+expr.toString()+"')");
       }
       for (Base nextLeft : left) {
-        if (tn.equals(nextLeft.fhirType())) {
+        if (compareTypeNames(tn, nextLeft.fhirType())) {
           result.add(nextLeft);
         }
       }
@@ -1797,9 +1823,19 @@ public class FHIRPathEngine {
     return result;
   }
 
+  private boolean compareTypeNames(String left, String right) {
+    if (doNotEnforceAsCaseSensitive) {
+      return left.equalsIgnoreCase(right);            
+    } else {
+      return left.equals(right);      
+    }
+  }
 
   private boolean isKnownType(String tn) {
     if (!tn.contains(".")) {
+      if (Utilities.existsInList(tn, "String", "Boolean", "Integer", "Decimal", "Quantity", "DateTime", "Time", "SimpleTypeInfo", "ClassInfo")) {
+        return true;
+      }
       try {
         return worker.fetchTypeDefinition(tn) != null;
       } catch (Exception e) {
@@ -4580,7 +4616,7 @@ public class FHIRPathEngine {
     if (!isKnownType(tn)) {
       throw new PathEngineException("The type "+tn+" is not valid");
     }
-    if (focus.size() > 1) {
+    if (!doNotEnforceAsSingletonRule && focus.size() > 1) {
       throw new PathEngineException("Attempt to use as() on more than one item ("+focus.size()+")");
     }
     
@@ -4599,7 +4635,7 @@ public class FHIRPathEngine {
         } else {
           StructureDefinition sd = worker.fetchTypeDefinition(b.fhirType());
           while (sd != null) {
-            if (tnp.equals(sd.getType())) {
+            if (compareTypeNames(tnp, sd.getType())) {
               result.add(b);
               break;
             }

org.hl7.fhir.r4b/src/test/java/org/hl7/fhir/r4b/test/FHIRPathTests.java

@@ -201,6 +201,9 @@ public class FHIRPathTests {
       }
     }
     
+    fp.setDoNotEnforceAsCaseSensitive(false);
+    fp.setDoNotEnforceAsSingletonRule(false);
+    
     if (node != null) {
       try {
         outcome = fp.evaluate(res, node);

org.hl7.fhir.r5/src/main/java/org/hl7/fhir/r5/utils/FHIRPathEngine.java

@@ -64,6 +64,7 @@ import org.hl7.fhir.utilities.MergedList;
 import org.hl7.fhir.utilities.MergedList.MergeNode;
 import org.hl7.fhir.utilities.SourceLocation;
 import org.hl7.fhir.utilities.Utilities;
+import org.hl7.fhir.utilities.VersionUtilities;
 import org.hl7.fhir.utilities.i18n.I18nConstants;
 import org.hl7.fhir.utilities.validation.ValidationOptions;
 import org.hl7.fhir.utilities.xhtml.NodeType;
@@ -264,6 +265,7 @@ public class FHIRPathEngine {
   private boolean doImplicitStringConversion;
   private boolean liquidMode; // in liquid mode, || terminates the expression and hands the parser back to the host
   private boolean doNotEnforceAsSingletonRule;
+  private boolean doNotEnforceAsCaseSensitive;
 
   // if the fhir path expressions are allowed to use constants beyond those defined in the specification
   // the application can implement them by providing a constant resolver 
@@ -373,8 +375,15 @@ public class FHIRPathEngine {
         primitiveTypes.add(sd.getName());
       }
     }
+    initFlags();
   }
 
+  private void initFlags() {
+    if (!VersionUtilities.isR5VerOrLater(worker.getVersion())) {
+      doNotEnforceAsCaseSensitive = true;
+      doNotEnforceAsSingletonRule = true;
+    }
+  }
 
   // --- 3 methods to override in children -------------------------------------------------------
   // if you don't override, it falls through to the using the base reference implementation 
@@ -465,6 +474,14 @@ public class FHIRPathEngine {
     this.doNotEnforceAsSingletonRule = doNotEnforceAsSingletonRule;
   }
 
+  public boolean isDoNotEnforceAsCaseSensitive() {
+    return doNotEnforceAsCaseSensitive;
+  }
+
+  public void setDoNotEnforceAsCaseSensitive(boolean doNotEnforceAsCaseSensitive) {
+    this.doNotEnforceAsCaseSensitive = doNotEnforceAsCaseSensitive;
+  }
+
   // --- public API -------------------------------------------------------
   /**
    * Parse a path for later use using execute
@@ -1804,7 +1821,7 @@ public class FHIRPathEngine {
         throw new PathEngineException("Attempt to use as on more than one item ("+left.size()+", '"+expr.toString()+"')");
       }
       for (Base nextLeft : left) {
-        if (tn.equals(nextLeft.fhirType())) {
+        if (compareTypeNames(tn, nextLeft.fhirType())) {
           result.add(nextLeft);
         }
       }
@@ -1812,6 +1829,13 @@ public class FHIRPathEngine {
     return result;
   }
 
+  private boolean compareTypeNames(String left, String right) {
+    if (doNotEnforceAsCaseSensitive) {
+      return left.equalsIgnoreCase(right);            
+    } else {
+      return left.equals(right);      
+    }
+  }
 
   private boolean isKnownType(String tn) {
     if (!tn.contains(".")) {
@@ -4617,7 +4641,7 @@ public class FHIRPathEngine {
         } else {
           StructureDefinition sd = worker.fetchTypeDefinition(b.fhirType());
           while (sd != null) {
-            if (tnp.equals(sd.getType())) {
+            if (compareTypeNames(tnp, sd.getType())) {
               result.add(b);
               break;
             }