remove excess logging from dag

The dag Update messages were not particularly helpful in the debugging
of terraform, and since we're going to be relying on DynamicExpand to an
even greater extent, this will eliminate a log of extra log output.

dag/walk.go

@@ -148,7 +148,6 @@ func (w *Walker) Wait() tfdiags.Diagnostics {
 // Multiple Updates can be called in parallel. Update can be called at any
 // time during a walk.
 func (w *Walker) Update(g *AcyclicGraph) {
-	log.Print("[TRACE] dag/walk: updating graph")
 	w.init()
 	v := make(Set)
 	e := make(Set)
@@ -181,7 +180,6 @@ func (w *Walker) Update(g *AcyclicGraph) {
 		w.wait.Add(1)
 
 		// Add to our own set so we know about it already
-		log.Printf("[TRACE] dag/walk: added new vertex: %q", VertexName(v))
 		w.vertices.Add(raw)
 
 		// Initialize the vertex info
@@ -212,8 +210,6 @@ func (w *Walker) Update(g *AcyclicGraph) {
 
 		// Delete it out of the map
 		delete(w.vertexMap, v)
-
-		log.Printf("[TRACE] dag/walk: removed vertex: %q", VertexName(v))
 		w.vertices.Delete(raw)
 	}
 
@@ -242,10 +238,6 @@ func (w *Walker) Update(g *AcyclicGraph) {
 
 		// Record that the deps changed for this waiter
 		changedDeps.Add(waiter)
-
-		log.Printf(
-			"[TRACE] dag/walk: added edge: %q waiting on %q",
-			VertexName(waiter), VertexName(dep))
 		w.edges.Add(raw)
 	}
 
@@ -266,10 +258,6 @@ func (w *Walker) Update(g *AcyclicGraph) {
 
 		// Record that the deps changed for this waiter
 		changedDeps.Add(waiter)
-
-		log.Printf(
-			"[TRACE] dag/walk: removed edge: %q waiting on %q",
-			VertexName(waiter), VertexName(dep))
 		w.edges.Delete(raw)
 	}
 
@@ -310,10 +298,6 @@ func (w *Walker) Update(g *AcyclicGraph) {
 		}
 		info.depsCancelCh = cancelCh
 
-		log.Printf(
-			"[TRACE] dag/walk: dependencies changed for %q, sending new deps",
-			VertexName(v))
-
 		// Start the waiter
 		go w.waitDeps(v, deps, doneCh, cancelCh)
 	}