Invalid reactions no longer reliably raise InputFileError

[speth]

Problem description

In Cantera 2.5, a YAML reaction definition without any rate constant information would raise an InputFileError showing the problematic reaction definition. Now, an error is thrown by ArrheniusBase::validate which does not show the corresponding input location.

Also, reactions containing undeclared species only produce the desired error message if the reaction rate is specified as a dict, but not if it is specified as a list.

Steps to reproduce

1. Create an input file with the following contents:

phases:
- name: gas
  thermo: ideal-gas
  species: [{h2o2.yaml/species: all}]
  kinetics: gas
  reactions: all
  state: {T: 300.0, P: 1 atm, X: {O2: 0.21, N2: 0.79}}

reactions:
- equation: 2 OH (+M) <=> H2O2 (+M)
  type: falloff
- equation: O + H2 <=> H + OH
- equation: CH3 + OH => CH3O + H
  rate-constant: {A: 1.0, b: 0, Ea: 0}
- equation: CH3 + OH => CH3O + H
  rate-constant: [0, 0, 0]

3. Import the phase in Python

Behavior

In Cantera 2.6.0, this raises an exception where an InputFileError is only given for the third reaction:

*******************************************************************************
CanteraError thrown by addReactions:

*******************************************************************************
CanteraError thrown by ArrheniusBase::validate:
Rate object for reaction '2 OH (+M) <=> H2O2 (+M)' is not configured.
*******************************************************************************

*******************************************************************************
CanteraError thrown by ArrheniusBase::validate:
Rate object for reaction 'H2 + O <=> H + OH' is not configured.
*******************************************************************************

*******************************************************************************
InputFileError thrown by Reaction::checkSpecies:
Error on line 12 of ./bad.yaml:
Reaction 'CH3 + OH => CH3O + H'
contains undeclared species: 'CH3', 'CH3O'
|  Line |
|     7 | 
|     8 | reactions:
|     9 | - equation: 2 OH (+M) <=> H2O2 (+M)
|    10 |   type: falloff
|    11 | - equation: O + H2 <=> H + OH
>    12 > - equation: CH3 + OH => CH3O + H
            ^
|    13 |   rate-constant: {A: 1.0, b: 0, Ea: 0}
|    14 | - equation: CH3 + OH => CH3O + H
|    15 |   rate-constant: [0, 0, 0]
*******************************************************************************

*******************************************************************************
CanteraError thrown by ArrheniusBase::validate:
Rate object for reaction 'CH3 + OH => CH3O + H' is not configured.
*******************************************************************************
*******************************************************************************

In Cantera 2.5.1, this input file produced useful error InputFileError messages for all four reactions:

***********************************************************************
CanteraError thrown by addReactions:

***********************************************************************
InputFileError thrown by AnyMap::operator[]:
Error on line 9 of ./bad.yaml:
Key 'low-P-rate-constant' not found.
Existing keys: equation, type
|  Line |
|     4 |   species: [{h2o2.yaml/species: all}]
|     5 |   kinetics: gas
|     6 |   reactions: all
|     7 | 
|     8 | reactions:
>     9 > - equation: 2 OH (+M) <=> H2O2 (+M)
            ^
|    10 |   type: falloff
|    11 | - equation: O + H2 <=> H + OH
|    12 | - equation: CH3 + OH => CH3O + H
***********************************************************************

***********************************************************************
InputFileError thrown by AnyMap::operator[]:
Error on line 11 of ./bad.yaml:
Key 'rate-constant' not found.
Existing keys: equation
|  Line |
|     6 |   reactions: all
|     7 | 
|     8 | reactions:
|     9 | - equation: 2 OH (+M) <=> H2O2 (+M)
|    10 |   type: falloff
>    11 > - equation: O + H2 <=> H + OH
            ^
|    12 | - equation: CH3 + OH => CH3O + H
|    13 |   rate-constant: {A: 1.0, b: 0, Ea: 0}
|    14 | - equation: CH3 + OH => CH3O + H
***********************************************************************

***********************************************************************
InputFileError thrown by Kinetics::addReaction:
Error on line 12 of ./bad.yaml:
Reaction 'CH3 + OH => CH3O + H' contains the undeclared species 'CH3'
|  Line |
|     7 | 
|     8 | reactions:
|     9 | - equation: 2 OH (+M) <=> H2O2 (+M)
|    10 |   type: falloff
|    11 | - equation: O + H2 <=> H + OH
>    12 > - equation: CH3 + OH => CH3O + H
            ^
|    13 |   rate-constant: {A: 1.0, b: 0, Ea: 0}
|    14 | - equation: CH3 + OH => CH3O + H
|    15 |   rate-constant: [0, 0, 0]
***********************************************************************

***********************************************************************
InputFileError thrown by Kinetics::addReaction:
Error on line 14 of ./bad.yaml:
Reaction 'CH3 + OH => CH3O + H' contains the undeclared species 'CH3'
|  Line |
|     9 | - equation: 2 OH (+M) <=> H2O2 (+M)
|    10 |   type: falloff
|    11 | - equation: O + H2 <=> H + OH
|    12 | - equation: CH3 + OH => CH3O + H
|    13 |   rate-constant: {A: 1.0, b: 0, Ea: 0}
>    14 > - equation: CH3 + OH => CH3O + H
            ^
|    15 |   rate-constant: [0, 0, 0]
***********************************************************************
***********************************************************************

System information

• Cantera version: 2.6.0

[ischoegl]

Good catch - the error message isn't ideal, but a fix should be relatively easy. Ideally, I'd like to prevent construction without a rate object to catch this much earlier, but I recall that there is a legacy FalloffReaction constructor that prevented that approach when constructing things from the Python interface. From that perspective, I'd like to defer a permanent fix until after Cantera/enhancements#149 is resolved.

[speth]

I ran into a (presumably related) case where ArrheniusBase::validate errors were coming up for reactions with undeclared species, rather than the expected InputFileError, and updated the example above accordingly.