PS: Helper predicates and classes.

Author: MathiasVP

powershell/ql/lib/semmle/code/powershell/ScriptBlock.qll

@@ -52,3 +52,12 @@ class ScriptBlock extends @script_block, Ast {
 
   final override Scope getEnclosingScope() { result = this }
 }
+
+/** A `process` block. */
+class ProcessBlock extends NamedBlock {
+  ScriptBlock scriptBlock;
+
+  ProcessBlock() { scriptBlock.getProcessBlock() = this }
+
+  ScriptBlock getScriptBlock() { result = scriptBlock }
+}

powershell/ql/lib/semmle/code/powershell/Variable.qll

@@ -169,6 +169,8 @@ private class AbstractVariable extends TVariable {
 
   abstract string getName();
 
+  final predicate hasName(string s) { this.getName() = s }
+
   abstract Scope getDeclaringScope();
 
   VarAccess getAnAccess() {
@@ -266,3 +268,7 @@ class Parameter extends AbstractLocalScopeVariable, TParameter {
     this.getAnAttribute().getANamedArgument() instanceof ValueFromPipelineAttribute
   }
 }
+
+class PipelineParameter extends Parameter {
+  PipelineParameter() { this.isPipeline() }
+}

powershell/ql/lib/semmle/code/powershell/controlflow/CfgNodes.qll

@@ -175,6 +175,32 @@ class ObjectCreationCfgNode extends CallCfgNode {
   string getConstructedTypeName() { result = objectCreation.getConstructedTypeName() }
 }
 
+private class NamedBlockChildMapping extends NonExprChildMapping, NamedBlock {
+  override predicate relevantChild(Ast n) { n = this.getAStmt() } // TODO: Handle getATrap
+}
+
+class NamedBlockCfgNode extends AstCfgNode {
+  NamedBlockChildMapping block;
+
+  NamedBlockCfgNode() { this.getAstNode() = block }
+
+  NamedBlock getBlock() { result = block }
+
+  StmtCfgNode getStmt(int i) { block.hasCfgChild(block.getStmt(i), this, result) }
+
+  StmtCfgNode getAStmt() { block.hasCfgChild(block.getAStmt(), this, result) }
+}
+
+private class ProcessBlockChildMapping extends NamedBlockChildMapping, ProcessBlock { }
+
+class ProcessBlockCfgNode extends NamedBlockCfgNode {
+  override ProcessBlockChildMapping block;
+
+  override ProcessBlock getBlock() { result = block }
+
+  PipelineParameter getPipelineParameter() { result = block.getEnclosingFunction().getAParameter() }
+}
+
 /** Provides classes for control-flow nodes that wrap AST expressions. */
 module ExprNodes {
   private class VarAccessChildMapping extends ExprChildMapping, VarAccess {

powershell/ql/lib/semmle/code/powershell/dataflow/internal/SsaImpl.qll

@@ -3,7 +3,9 @@ private import powershell
 private import semmle.code.powershell.Cfg as Cfg
 private import semmle.code.powershell.controlflow.internal.ControlFlowGraphImpl as ControlFlowGraphImpl
 private import semmle.code.powershell.dataflow.Ssa
-private import Cfg::CfgNodes::ExprNodes
+import Cfg::CfgNodes
+private import ExprNodes
+private import StmtNodes
 
 module SsaInput implements SsaImplCommon::InputSig<Location> {
   private import semmle.code.powershell.controlflow.ControlFlowGraph as Cfg

powershell/ql/lib/semmle/code/powershell/internal/Argument.qll

@@ -7,10 +7,10 @@ module Private {
    * The argument may be named or positional.
    */
   abstract class AbstractArgument extends Expr {
-    Ast call;
+    Call call;
 
     /** Gets the call that this is an argumnt of. */
-    final Ast getCall() { result = call }
+    final Call getCall() { result = call }
 
     /** Gets the position if this is a positional argument. */
     abstract int getPosition();
@@ -23,7 +23,7 @@ module Private {
   }
 
   class CmdArgument extends AbstractArgument {
-    override Cmd call;
+    override CmdCall call;
 
     CmdArgument() { call.getAnArgument() = this }
 
@@ -34,10 +34,10 @@ module Private {
     final override predicate isQualifier() { none() }
   }
 
-  class InvokeArgument extends AbstractArgument {
-    override InvokeMemberExpr call;
+  class MethodArgument extends AbstractArgument {
+    override MethodCall call;
 
-    InvokeArgument() { call.getAnArgument() = this or call.getQualifier() = this }
+    MethodArgument() { call.getAnArgument() = this or call.getQualifier() = this }
 
     override int getPosition() { call.getArgument(result) = this }