Avoid `instanceof` which leads to runtime errors with deep npm dependencies

[accordproject]

Avoid `instanceof` which leads to runtime errors with deep npm dependencies

[dselman]

Reopening based on further investigation and how it interacts with Babel:
accordproject/web-components#110

[jeromesimeon]

There still seems to be a few occurrences of instance of around:

bash-3.2$ grep -r instanceof lib
lib/serializer/typedstack.js:        if(expectedType && !(obj instanceof expectedType)) {
lib/serializer/typedstack.js:        if(expectedType && !(result instanceof expectedType)) {
lib/serializer/jsonpopulator.js:        if (thing instanceof ClassDeclaration) {
lib/serializer/jsonpopulator.js:        } else if (thing instanceof RelationshipDeclaration) {
lib/serializer/jsonpopulator.js:        } else if (thing instanceof Field) {
lib/serializer/instancegenerator.js:        if (thing instanceof ClassDeclaration) {
lib/serializer/instancegenerator.js:        } else if (thing instanceof RelationshipDeclaration) {
lib/serializer/instancegenerator.js:        } else if (thing instanceof Field) {
lib/serializer/instancegenerator.js:        if (classDeclaration instanceof EnumDeclaration) {
lib/serializer/resourcevalidator.js:        if (thing instanceof EnumDeclaration) {
lib/serializer/resourcevalidator.js:        } else if (thing instanceof ClassDeclaration) {
lib/serializer/resourcevalidator.js:        } else if (thing instanceof RelationshipDeclaration) {
lib/serializer/resourcevalidator.js:        } else if (thing instanceof Field) {
lib/serializer/resourcevalidator.js:        if(!((obj instanceof Resource) || (obj instanceof Concept))) {
lib/serializer/resourcevalidator.js:        if(obj instanceof Identifiable) {
lib/serializer/resourcevalidator.js:                    if(obj instanceof Identifiable) {
lib/serializer/resourcevalidator.js:        if(obj instanceof Identifiable) {
lib/serializer/resourcevalidator.js:        if(field.isArray() && !(obj instanceof Array)) {
lib/serializer/resourcevalidator.js:        if(!(obj instanceof Array)) {
lib/serializer/resourcevalidator.js:            if(obj instanceof Identifiable) {
lib/serializer/resourcevalidator.js:            if(!(obj instanceof Array)) {
lib/serializer/resourcevalidator.js:        if(obj instanceof Relationship) {
lib/serializer/resourcevalidator.js:        } else if (obj instanceof Resource && (this.options.convertResourcesToRelationships || this.options.permitResourcesForRelationships)) {
lib/serializer/resourcevalidator.js:        if(value instanceof Identifiable) {
lib/serializer/jsongenerator.js:        if (thing instanceof ClassDeclaration) {
lib/serializer/jsongenerator.js:        } else if (thing instanceof RelationshipDeclaration) {
lib/serializer/jsongenerator.js:        } else if (thing instanceof Field) {
lib/serializer/jsongenerator.js:        if (!((obj instanceof Resource) || (obj instanceof Concept))) {
lib/serializer/jsongenerator.js:        if (obj instanceof Identifiable && this.deduplicateResources) {
lib/serializer/jsongenerator.js:                if (this.permitResourcesForRelationships && item instanceof Resource) {
lib/serializer/jsongenerator.js:        } else if (this.permitResourcesForRelationships && obj instanceof Resource) {
lib/serializer/jsongenerator.js:        if (relationshipOrResource instanceof Resource) {
lib/factory.js:        if (!(classDeclaration instanceof TransactionDeclaration)) {
lib/factory.js:        if (!(classDeclaration instanceof EventDeclaration)) {
lib/introspect/parser.pegjs:InstanceofToken = "instanceof" !IdentifierPart
lib/introspect/modelfile.js:        if(classDeclaration instanceof AssetDeclaration) {
lib/introspect/modelfile.js:        if(classDeclaration instanceof TransactionDeclaration) {
lib/introspect/modelfile.js:        if(classDeclaration instanceof EventDeclaration) {
lib/introspect/modelfile.js:        if(classDeclaration instanceof ParticipantDeclaration) {
lib/introspect/modelfile.js:            if(classDeclaration instanceof type && (includeSystemType || !classDeclaration.isSystemType())) {
lib/introspect/parser.js:            escapedParts += expectation.parts[i] instanceof Array
lib/introspect/parser.js:      peg$c182 = "instanceof",
lib/introspect/parser.js:      peg$c183 = peg$literalExpectation("instanceof", false),
lib/model/typed.js:            if (field instanceof Field) {
lib/serializer.js:        if(!(resource instanceof Typed)) {
lib/serializer.js:        if (classDeclaration instanceof TransactionDeclaration) {
lib/serializer.js:        } else if (classDeclaration instanceof EventDeclaration) {
lib/serializer.js:        } else if (classDeclaration instanceof ConceptDeclaration) {
lib/serializer.js:        } else if (classDeclaration instanceof EnumDeclaration) {

[jeromesimeon]

Confirming that this works. The approach is to override hasInstance in the corresponding classes, which effectively underlies the implementation for instanceof.